Force and Laws of Motion

Forces that are equal in magnitude but opposite in direction are called:

To maintain the motion of an object with constant velocity, the net force required is:

An unbalanced force can change which of the following?

If three forces of $2\text{ N}$, $3\text{ N}$, and $5\text{ N}$ all act on a body in the same direction, the resultant force is:

A satellite orbits the Earth in a circular path at a constant speed, as shown in the diagram. According to the laws of motion, which of the following statements is true regarding the forces acting on the satellite?

A force of $10\,N$ acts on a body. To make the net force zero, another force of:

Balanced forces can change which of the following properties of a rubber ball?

An object is subjected to two perpendicular forces: $3\text{ N}$ along the X-axis and $4\text{ N}$ along the Y-axis. What is the magnitude of the unbalanced force?

If a force of $5\text{ N}$ acts on a body of mass $2\text{ kg}$ and a force of $10\text{ N}$ acts on a body of mass $4\text{ kg}$, which body has a greater acceleration?

A spring is compressed between two blocks of different masses. When released, the blocks move in opposite directions. The forces acting on the blocks during the expansion are:

An object of mass $2\text{ kg}$ is sliding with a constant velocity of $4\text{ m/s}$ on a frictionless horizontal table. The force required to keep the object moving with the same velocity is:

Inertia of rest is the tendency of an object to:

When a car stops suddenly, why do we use seat belts?

If an object is moving with constant speed along a straight line, the net force on it is:

A block is pushed along a frictionless horizontal surface from point $A$ to point $B$ by a constant force $F$. At point $B$, the force is completely removed, and the block continues to move toward point $C$. According to the First Law of Motion, which statement best describes the motion of the block between points $B$ and $C$?

An athlete in a hammer throw event swings a heavy metallic ball in a circular path. If the athlete releases the wire at the exact moment the ball is at position $P$ as shown in the diagram, the ball travels along the straight line path $PX$. This phenomenon is a direct result of which property?

If an object is at rest, we can conclude that:

A system consists of three blocks $P$, $Q$, and $R$ stacked vertically ($P$ on top, $R$ at the bottom) on a frictionless horizontal plane. The contact surfaces between all blocks are also perfectly frictionless. If a massive horizontal force $F$ is applied to the middle block $Q$, causing it to be extracted from the stack almost instantaneously, which of the following best describes the horizontal motion of blocks $P$ and $R$ relative to the ground according to the First Law of Motion?

When a marble is rolled on a horizontal surface, it stops after some time. This observation does not violate Newton's first law because:

The property of inertia is most closely related to which physical quantity?

A constant force of $2\text{ N}$ acts on a $2\text{ kg}$ mass for $2\text{ seconds}$. What is the change in velocity?

If you push a heavy box and a light box with the same force, which one will have a higher acceleration?

In the equation $F = \Delta p / \Delta t$, what does $\Delta p$ represent?

The SI unit of force is named after which scientist?

The momentum of a body of mass $100\,g$ moving with a velocity of $10\,m/s$ is:

Two bodies have masses in the ratio $3:4$. When the same force is applied to both, the ratio of their accelerations is:

A passenger in a moving train tosses a coin which falls behind him. This means that motion of the train is:

Two blocks, $X$ and $Y$, are initially at rest on a frictionless horizontal surface. Block $X$ has a mass of $m$ and block $Y$ has a mass of $3m$. A constant force $F_X$ is applied to block $X$ for a time interval $t$, causing it to reach a velocity $v$. A constant force $F_Y$ is applied to block $Y$ for a time interval $2t$, causing it to reach a velocity $4v$. Based on the Second Law of Motion, what is the ratio of the force $F_X$ to the force $F_Y$?

If the force acting on a body is tripled and the mass is doubled, what is the ratio of the new acceleration to the old acceleration?

A force $F$ produces an acceleration $a$ in a body of mass $m$. If the same force is applied to another body of mass $m'$, it produces an acceleration $2a$. The mass $m'$ is:

According to the third law of motion, a single force ____ exists in nature.

When you push a swinging door, the door pushes back on your hand with:

In a Newton’s Cradle, when one ball hits the others, the last ball flies off. This demonstrates:

When catching a fast-moving cricket ball, the ball exerts a force on your hand. Your hand exerts a force on the ball that is:

A person is standing on a weighing machine in a lift. If the lift is at rest, the reading of the machine is the reaction force to the person's:

During the recoil of a gun, why is the recoil velocity low?

A stone is thrown upwards. While it is in the air, the action-reaction pair for the force of gravity is:

A ball of mass $m$ falls from a height $h$ and rebounds to the same height. The impulse delivered by the floor to the ball is:

In an elastic collision between two bodies of equal mass, if one body is at rest and the other strikes it with velocity $v$:

A man is paddling a boat in a river. If he stops paddling, the boat eventually stops. This is because:

If the net force on an object is directed towards the North, the object will accelerate towards the:

A book placed on a horizontal table is acted upon by two forces: weight and normal force. If the book is at rest, these forces are:

If you push a toy car and it moves faster and faster, you are applying:

Which of these can be changed by an unbalanced force?

Which of the following describes the state of a parachutist falling at terminal velocity (constant speed)?

What is the net force when two forces of $20\ N$ and $30\ N$ act on a body in opposite directions?

A ball is rolling on a smooth floor. To increase its speed, what must be done?

When a marble is released from the top of an inclined plane, it rolls down and then moves on a horizontal surface. It eventually stops. What is the primary reason for it stopping on the horizontal surface?

Which of the following does NOT affect the magnitude of the maximum static frictional force between two solid surfaces?

A force $F$ produces an acceleration $a$ in a body of mass $m$. If the same force $F$ is applied to another body of mass $2m$, the acceleration produced will be:

The total momentum of two objects before a collision is equal to the total momentum after the collision if no external force acts. This is linked to which law?

While rowing a boat, the rower pushes the water backwards. This is the:

If the action force is $F_{12}$ and reaction force is $F_{21}$, then which is true?

When a bird is gliding, it pushes the air down. The reaction force is:

Why does a gun recoil with much less velocity than the velocity of the bullet?

The recoil of a gun is a phenomenon that demonstrates that the total momentum of the gun and bullet system before firing is ___________ the total momentum after firing.

A man of mass $80 \text{ kg}$ pushes a wall with $100 \text{ N}$ force. The acceleration of the man would be:

A car is traveling at a constant speed along a straight road. A small coin is placed on the dashboard, which is perfectly smooth and frictionless. If the car suddenly takes a sharp turn to the left, which of the following best describes the path of the coin according to an observer watching from a stationary hot air balloon directly above the car?

A large, smooth, frictionless table is fixed inside a train carriage. A small steel ball is placed on the center of the table while the train is stationary. If the train suddenly accelerates forward at $2\text{ m/s}^2$, which of the following correctly describes the acceleration of the ball as measured by an observer standing on the ground and an observer sitting in the train?

Two magnets are placed on two different carts. North pole of Magnet A faces the North pole of Magnet B. They repel each other. If Magnet A is much stronger than Magnet B:

What is the momentum of a $0.5\text{ kg}$ ball moving at $10\text{ m/s}$?

The total momentum of an isolated system remains constant. This is the Law of:

An object of mass $2\text{ kg}$ moving at $10\text{ m/s}$ has the same momentum as an object of mass $4\text{ kg}$ moving at:

High-jump athletes are made to fall on a cushioned bed to:

An object of mass $2 \space kg$ is moving with an initial velocity of $4 \space m/s$. A constant force of $6 \space N$ is applied for $3 \space s$ in the direction of motion. What is the final momentum of the object?

A fielder is able to catch a cricket ball safely by pulling his hands along with the ball. This is because it results in:

If a net force of $1 \space N$ acts on a $1 \space kg$ body, the body moves with:

A $1000 \space kg$ rocket is fired vertically upwards. If the exhaust gases are ejected at a rate of $5 \space kg/s$ with a velocity of $400 \space m/s$, what is the upward force (thrust) on the rocket?

A force $F$ is applied to a body of mass $m$ at rest for a time interval $\Delta t$. If $K$ is the kinetic energy acquired by the body, then $K$ is proportional to:

The momentum of a particle is given by $p = At^2 + Bt$. The force acting on the particle at $t = 1 \space s$ is:

What happens when an unbalanced force acts on an object?

If you apply a force of $20 N$ to the right and someone else applies $20 N$ to the left on the same object, what is the net force?

Which of the following forces is always attractive in nature?

Opening a door by its handle involves:

An object is being acted upon by two horizontal forces as shown in the diagram: $10\ N$ to the left and $15\ N$ to the right. What is the magnitude and direction of a third force, $F_3$, that must be applied to the object so that the resulting net force is $5\ N$ towards the left?

Water tankers are often provided with internal baffles (partitions). This is to reduce the effect of:

A force of $25\ N$ is applied to an object of mass $m$, resulting in an acceleration of $5\ m/s^2$. What is the mass of the object?

Qualitatively, Newton's first law of motion defines:

If the momentum of a body is doubled, its kinetic energy becomes:

Two bodies of masses $m$ and $4m$ are moving with equal momentum. The ratio of their velocities is:

Which of the following is true about the nature of surfaces and friction?

If the weight of an object is increased, the force of friction between it and the ground will:

The soles of our shoes wear out after long use because of:

A book sliding on a table eventually stops. Why?

A block is resting on a rough horizontal floor. A student applies an additional vertical downward force $V$ on the block as shown in the diagram. What is the effect of this downward force on the limiting friction (maximum static friction) between the block and the floor?

Which of the following will have the highest drag when moving through water at the same speed?

If the surface area of contact is doubled, keeping the weight and nature of surfaces the same, the force of friction:

A $10\text{ kg}$ block is resting on a long horizontal conveyor belt. The belt starts moving with a constant horizontal acceleration of $5\text{ m/s}^2$. If the coefficient of static friction is $0.4$ and the coefficient of kinetic friction is $0.3$, what is the magnitude of the frictional force acting on the block? (Take $g = 10\text{ m/s}^2$)

If you push a heavy cabinet and it doesn't move, the static friction is exactly equal to your push. If you push harder and it still doesn't move, the static friction:

When a box is pushed on a floor, the force of friction acts:

If you are sitting in a car and the driver turns left sharply, your body moves towards the:

Which of the following is true for an object moving with constant velocity?

The property of inertia is possessed by:

Newton's First Law is valid in:

A block of mass $5 \text{ kg}$ is moving on a frictionless horizontal surface with a constant velocity of $10 \text{ m/s}$ towards the right. Two forces, $F_1 = 15 \text{ N}$ and $F_2 = 15 \text{ N}$, are applied to the block in opposite directions as shown. According to Newton's First Law of Motion, what will be the velocity of the block after $5 \text{ seconds}$ of the application of these forces?

A stone tied to a string is being whirled in a horizontal circle at a constant speed. If the string suddenly breaks when the stone is at the position shown in the diagram, which path will the stone follow immediately after the break?

If the mass of a body is $5 \text{ kg}$, its inertia compared to a body of $10 \text{ kg}$ is:

When we stop rowing a boat, it comes to a stop after some time. This is due to:

Galileo argued that a body would continue to move with constant velocity if:

If the mass of a body is doubled, its inertia becomes:

When we stop pedaling a bicycle, it slows down because of:

The momentum of an object depends on:

Qualitative definition of force is given by Newton's First Law, while quantitative definition is given by:

If two bodies of different masses have the same momentum, the lighter body will have:

A force of $0.6\text{ N}$ acts on a body of mass $100\text{ g}$ that is initially at rest. If this force is applied continuously for a duration of $5\text{ seconds}$, what will be the final velocity of the body?

Two objects, $X$ and $Y$, have the same initial momentum. They are both brought to rest by applying external forces $F_X$ and $F_Y$ respectively. Based on the stopping times shown in the diagram, what is the relationship between the two forces?

A rubber ball of mass $0.2\text{ kg}$ travels toward a wall and bounces back as illustrated. If the ball hits the wall at $5\text{ m/s}$ and returns with the same speed in the opposite direction, what is the magnitude of the change in momentum?

A block of mass $2\text{ kg}$ is placed on a smooth horizontal surface. Two forces $F_1 = 20\text{ N}$ and $F_2 = 10\text{ N}$ act on the block in the same direction. What is the acceleration?

If the time of impact in a collision is increased by a factor of 3 while the change in momentum remains constant, the average force will:

A shell of mass $0.02\text{ kg}$ is fired by a gun of mass $100\text{ kg}$. If the muzzle speed of the shell is $80\text{ m/s}$, what is the recoil speed of the gun?

In space, a rocket can accelerate because:

A book placed on a table is at rest. The force of the book on the table and the force of the table on the book are:

If a mosquito hits the windshield of a moving truck, the force exerted by the truck on the mosquito is:

The magnitude of the recoil force on a gun is ________ the force on the bullet.

A compressed spring is held between two blocks A and B. When released, the spring pushes A to the left and B to the right. The forces on A and B are:

When a hammer hits a nail, the hammer:

If you are standing in a boat and you walk from one end to the other, the boat moves in the ______ direction.

A bird flies by pushing the air downwards with its wings. The reaction force is:

Newton's Third Law explains why it is difficult to:

An object is placed on a table. The action is the force of the object on the table. The reaction is the force of the table on the object. If the table suddenly breaks, the reaction force:

Which of these is not an effect of force?

An unbalanced force acts on a body. Which of the following can never be zero?

The direction of momentum is the same as the direction of:

When we jump out of a boat in the forward direction, the boat moves:

Two blocks of masses $2\text{ kg}$ and $3\text{ kg}$ are connected by a light string on a frictionless horizontal surface. A horizontal force of $5\text{ N}$ is applied to the $2\text{ kg}$ block towards the left, while a horizontal force of $20\text{ N}$ is applied to the $3\text{ kg}$ block towards the right. What is the magnitude of the acceleration of the system?

A $4\text{ kg}$ block (A) is placed on a frictionless horizontal table and connected by a light string to a $1\text{ kg}$ block (B) hanging over the edge via a frictionless pulley. If the system is released from rest and $g = 10\text{ m/s}^2$, what is the magnitude of the acceleration of the system?

What is the relation between the Newton ($N$) and Dyne ($dyn$)?

A block of mass $m$ is sliding down a frictionless inclined plane of angle $\theta$. What is the net force acting on the block parallel to the incline?

A person of mass $50\text{ kg}$ jumps from a height of $5\text{ m}$ onto the ground. If he does not bend his knees and comes to rest in $0.1\text{ s}$, what is the average force exerted by the ground on his feet? (Take $g = 10\text{ m/s}^2$)

A force $F$ is applied to a system of three blocks of masses $m$, $2m$, and $3m$ connected by strings. If the blocks are moving on a frictionless surface, what is the tension in the string between the $2m$ and $3m$ blocks (force $F$ is applied to the $3m$ block)?