Laws of Motion

The product of force and the time for which it acts is called:

A constant force acts on a body of mass $2\text{ kg}$ and changes its velocity from $3\text{ m/s}$ to $7\text{ m/s}$ in $2\text{ seconds}$. What is the magnitude of the force?

Which of the following describes the relationship between mass and inertia?

A body is accelerating. This implies that:

A block of mass $M$ is pulled along a horizontal frictionless surface by a rope of mass $m$. A force $P$ is applied at the free end of the rope. The force exerted by the rope on the block is:

A body of mass $m$ is moving on a rough horizontal surface with coefficient of kinetic friction $μ_k$. The retardation of the body is:

In a tug of war, the winning team is the one that:

Three forces $F_1, F_2, F_3$ are acting on a particle of mass $m$ such that $\vec{F}_1 + \vec{F}_2 + \vec{F}_3 = 0$. If the force $F_1$ is removed, the acceleration of the particle will be:

A particle of mass $m$ is moving with a velocity $v$ along a straight line. A force $F$ is applied for time $t$ to double its momentum. The force $F$ must be:

A balloon of mass $M$ is descending with an acceleration $a$ ($a < g$). How much mass should be removed from it so that it starts moving up with an acceleration $a$?

A $0.2\text{ kg}$ ball moving at $10\text{ m/s}$ is stopped by a player in $0.1\text{ s}$. The force exerted by the player is:

A lighter body and a heavier body have the same kinetic energy. Which one has a larger momentum?

The rate of change of momentum is proportional to:

If a system consists of two particles with momenta $\vec{p_1}$ and $\vec{p_2}$, the total momentum $\vec{P}$ is:

If the external force acting on a system is zero, then the center of mass:

Two bodies $A$ and $B$ of mass $m$ and $2m$ respectively are moving with velocities $2v$ and $v$ respectively. Which of the following is true?

A $60\text{ kg}$ man is in a $100\text{ kg}$ boat floating on water. He walks from one end of the boat to the other, a distance of $4\text{ m}$. The boat moves a distance $s$ in the water. What is $s$?

A trolley of initial mass $M_0$ is pulled from rest by a constant horizontal force $F$ on a smooth surface. At $t = 0$, sand begins to fall vertically into the trolley from a stationary hopper at a constant rate of $\mu \text{ kg/s}$. Assuming the sand stays in the trolley, the velocity $v$ of the trolley at any time $t$ is given by:

Block A (mass $m$) and Block B (mass $2m$) are connected by a light spring of constant $k$ and are initially at rest on a frictionless horizontal surface. A third block C (mass $m$) moving with a velocity $v_0$ along the line joining A and B strikes block A and sticks to it. What is the maximum potential energy stored in the spring during the subsequent motion of the system?

A projectile of mass $M$ is traveling in a horizontal direction with a velocity $V$. It suddenly explodes into two fragments of masses $m_1$ and $m_2$ ($M = m_1 + m_2$). If the explosion releases an internal energy $\Delta E$ which is entirely converted into the kinetic energy of the fragments, the magnitude of the relative velocity $v_{rel}$ between the two fragments after the explosion is:

When a person stands still on the ground, the ground pushes up on the person with a force equal to their weight. This is an example of:

The resultant of two forces $P$ and $Q$ acting at an angle of $180^\circ$ is:

A mass of $5 \text{ kg}$ is hanging by a string in an elevator moving up at a constant speed of $2 \text{ m/s}$. The tension in the string is: (Take $g = 10 \text{ m/s}^2$)

In a free-body diagram of a particle in equilibrium, we represent:

A block of mass $M$ is suspended by a string. Another string is attached to the bottom of the block. If the bottom string is pulled slowly, which string will break first?

A mass of $5\text{ kg}$ is suspended by two strings making angles $60^\circ$ and $60^\circ$ with the horizontal. The tension in each string is ($g = 10\text{ m/s}^2$):

A particle moves with a constant velocity $\vec{v}$. This implies that:

A particle is in equilibrium under the action of forces $\vec{F_1}, \vec{F_2}, \dots, \vec{F_n}$. If $\vec{F_k}$ is the $k$-th force, then $\sum_{k=1}^n \vec{F_k} = 0$. If one force $\vec{F_i}$ is removed, the resultant of the remaining forces is:

A small bead of mass $m$ can move on a smooth vertical wire in the shape of $y = x^4/b^3$. If a horizontal force $F$ is applied, the equilibrium height $y$ is:

Two strings of lengths $l$ and $2l$ are attached to a mass $m$ and to two points $A$ and $B$ in a horizontal line. If the strings are perpendicular to each other, the tension in the shorter string is:

Which of the following properties of kinetic friction is true?

Which of the following statements is true for a block sitting on a horizontal table with no external horizontal force applied?

If $\phi$ is the angle of friction, the coefficient of static friction $\mu_s$ is:

Rolling friction occurs when:

A block of mass $m$ is on a horizontal surface with coefficient of friction $\mu$. If a force $F = mg/2$ is applied horizontally and the block doesn't move, the friction force is:

Static friction is called a 'self-adjusting force' because:

A block of mass $2\text{ kg}$ is lying on a rough horizontal plane. The coefficient of static friction is $0.5$. The magnitude of the maximum horizontal force that can be applied on the block without moving it is: (Take $g = 10\text{ m/s}^2$)

Two blocks of masses $m_1 = 4\text{ kg}$ and $m_2 = 2\text{ kg}$ are connected by a light inextensible string and placed on a rough inclined plane which makes an angle of $37^{\circ}$ with the horizontal. The $4\text{ kg}$ block is placed lower than the $2\text{ kg}$ block. The coefficient of kinetic friction between the $4\text{ kg}$ block and the plane is $\mu_1 = 0.2$, and between the $2\text{ kg}$ block and the plane is $\mu_2 = 0.5$. If the system is released from rest, the tension in the string is (Take $g = 10\text{ m/s}^2$, $\sin 37^{\circ} = 0.6$, and $\cos 37^{\circ} = 0.8$):

Which of the following is true about the coefficient of friction?

Two masses $m_1$ and $m_2$ are connected by a string over a pulley. $m_1$ is on a rough surface with $\mu$. $m_2$ is hanging. If $m_2$ is replaced by $m_3$ such that the system moves with constant velocity, then $m_3$ is:

What happens to the direction of the centripetal force as the body moves along the circle?

If the speed and radius are both doubled, the centripetal acceleration:

The magnitude of centripetal force can be written using frequency $f$ as:

For a body in uniform circular motion, the change in kinetic energy after one complete revolution is:

The time period of a particle in uniform circular motion is $4\text{ s}$. The time taken by the particle to cover an angular displacement of $\pi/3$ radians is:

A small sphere of mass $m$ is suspended by a thread of length $l$ and is rotated in a horizontal circle. If the thread makes an angle $\theta$ with the vertical, the tension in the thread is:

If the radius of a circular path is doubled, but the centripetal force is kept constant, how must the speed change?

For a particle in uniform circular motion, the acceleration vector $\vec{a}$ at a point $P(r, \theta)$ on the circle of radius $R$ is given by (where $\theta$ is measured from the x-axis):

A sphere is suspended by a thread of length $l$. What minimum horizontal velocity must be imparted to the sphere for it to reach the height of the suspension?

A fly is sitting on a record player rotating at $45\text{ rpm}$. The fly is $10\text{ cm}$ from the center. What is its centripetal acceleration?

If a net force $F$ acts on a mass $m$, it produces an acceleration $a$. If $F$ is removed, the acceleration becomes:

In a vacuum, if you drop a feather and a hammer, they fall at the same rate. This experiment relates to whose work?

Galileo’s work shifted the focus from 'Why do things move?' to:

What happens to the velocity of an object if the net external force is zero?

The property of an object that resists a change in its state of motion is quantified by its:

In the absence of air resistance, if a heavy ball and a light ball are dropped from the same height:

Aristotle's view on motion is categorized as a 'fallacy' because it is:

A body of mass $2\text{ kg}$ is moving with a velocity of $10\text{ m/s}$ on a frictionless horizontal surface. The force required to maintain this velocity is:

In the CBSE Class 11 textbook, the discussion of Aristotle's Fallacy serves as a precursor to which law?

Galileo’s experiments with inclined planes allowed him to 'dilute' which force, making it easier to measure the motion of objects?

An object of mass $m$ is moving on a smooth horizontal surface with constant velocity $v$. The force required to keep the object moving with the same velocity is:

Which of the following has the least inertia?

A passenger sitting in a train at rest is looking out of the window. Another train passes by slowly. The passenger feels as if his train is moving. This is due to:

When a moving car turns a corner, the passengers are thrown outwards. This is an example of:

A $4\, kg$ block is sliding on a frictionless horizontal surface and is acted upon by three horizontal forces as described. Force $F_1 = 15\, N$ acts towards the right, while $F_2 = 7\, N$ and $F_3 = P$ act towards the left. According to the Law of Inertia, if the block is observed to maintain a constant velocity of $6\, m/s$ towards the right, what is the magnitude of the force $P$?

The concept of inertia was first introduced by:

When a ball is thrown vertically upwards, at the highest point its velocity is zero. Is it in equilibrium?

A ball is placed on the perfectly smooth, horizontal floor of a train carriage moving along a straight track at a constant velocity $\vec{v}$. Three observers—$P$ (standing still on the platform), $Q$ (sitting inside the train), and $R$ (in a car moving with a constant acceleration $\vec{a}$ on a parallel road)—monitor the ball's motion. Which of these observers will perceive the ball's state as a direct validation of the Law of Inertia (i.e., observing zero acceleration because the net force is zero)?

In an inertial frame, an object with no net force acting on it must have:

Which of these is NOT a correct statement about inertia?

The work done by a centripetal force is always:

Centrifugal force is a ____ force.

If the net force on a particle is zero, then its velocity:

When a force acts on a spring, the restoring force acts in the ____ direction of the displacement.

Two masses $m_1=4kg$ and $m_2=6kg$ are connected by a string passing over a frictionless pulley. The acceleration of the system is: (Take $g = 10 \, m/s^2$)

A man slides down a light rope whose breaking strength is $\eta$ times his weight ($\eta < 1$). The maximum acceleration of the man so that the rope does not break is:

A bomb at rest explodes into three fragments of equal mass. Two fragments fly off at right angles to each other with velocities $9 \, m/s$ and $12 \, m/s$. The speed of the third fragment is:

Which of the following statements about friction is true?

A stone of mass $m$ is tied to a string and whirled in a vertical circle of radius $r$. The difference in tension at the lowest and highest points is:

A body of mass $M$ is moving in a circle of radius $R$ with constant speed $v$. The work done by the centripetal force in one-fourth of a revolution is:

If a force of $12\,N$ and $5\,N$ act on a body at $90^{\circ}$ to each other, the magnitude of the resultant force is:

What is the net force acting on a rain drop falling with a constant velocity?

The value of coefficient of friction depends on:

A bomb at rest explodes into two pieces. The pieces fly off in:

A block of mass $m$ is being pulled by a string with tension $T$ at an angle $\theta$ to the horizontal. The normal reaction $N$ on the block is:

A body of mass $2\,kg$ moves with an acceleration of $3\,m/s^2$. The change in momentum in $4\,s$ is:

In a tug-of-war, the team that exerts a larger force on _______ wins.

A block of mass $m$ is placed on a surface with a vertical cross-section given by $y = x^3/6$. If the coefficient of friction is $0.5$, what is the maximum height above the ground at which the block can be placed without slipping?

A cricket ball of mass $150 \\text{ g}$ is moving with a velocity of $12 \\text{ m/s}$ and is hit by a bat so that the ball is turned back with a velocity of $20 \\text{ m/s}$. The force of blow acts for $0.01 \\text{ s}$. What is the average force exerted on the ball by the bat?

A system of two blocks $m_1$ and $m_2$ connected by a string is placed on a rough horizontal surface. A force $F$ pulls $m_2$. If $m_2 > m_1$ and the coefficient of friction is $\mu$ for both, what is the tension in the string?