Motion, Forces and Energy

To find the average thickness of a wire from a single measurement using a micrometer, what should the student do first?

Which of the following describes weight?

Convert $750\ milliliters$ ($ml$) to liters ($L$).

Which of these is a unit of volume?

A block of metal has a density of $8000\ kg/m^{3}$. What is the mass of a $0.002\ m^{3}$ piece of this metal?

A student wants to measure the time for a ball to fall $2.0\ m$. Which of the following would improve the accuracy of the result?

In the measurement $0.00340\ kg$, how many significant figures are there?

A digital balance shows a reading of $0.00\ g$. When a small object is placed on it, it shows $1.45\ g$. When the object is removed, it shows $-0.02\ g$. What is the correct mass of the object?

An object travels at $20\ m/s$ at an angle of $60^\circ$ to the horizontal. What are the horizontal and vertical components of its velocity?

Which of the following represents the most accurate measurement of a length of $5\ cm$?

A truck travels $60\text{ km}$ in $1.5\text{ hours}$. What is its average speed?

If speed is represented by $v$ and distance by $d$, which formula correctly gives the time $t$?

An object covers equal distances in equal intervals of time. This describes...

A boat crosses a $120\text{ m}$ wide river in $30\text{ s}$. What is its average speed?

The velocity-time graph below represents the motion of a toy car. What is the distance traveled by the car during the time interval when its acceleration is $0\text{ m/s}^2$?

The gradient of a speed-time graph represents:

A ticker-tape timer produces 50 dots per second. If there is a distance of $10\text{ cm}$ between 5 consecutive gaps, what is the average speed of the tape?

An object moves $10\text{ m}$ North, then $10\text{ m}$ West, and then $10\text{ m}$ South. What is the magnitude of the displacement?

A body starts from rest and moves with a uniform acceleration of $2\text{ m/s}^2$ for $10\text{ s}$ and then with a uniform deceleration of $4\text{ m/s}^2$ until it stops. What is the total distance traveled?

If the acceleration of an object is proportional to its displacement from a fixed point but in the opposite direction, the motion is:

If the density of a substance is $2500\ kg/m^3$, what is the mass of $0.1\ m^3$ of this substance?

What happens to the weight of an object as it is moved further away from the center of the Earth?

To find the density of a regular wooden cube, which two instruments are needed?

An object floats in a liquid. The weight of the object is equal to:

Which of the following defines density?

A measuring cylinder contains some liquid. When an additional $30\ g$ of the same liquid is added, the volume increases by $25\ cm^3$. What is the density of the liquid?

A planet has twice the mass of Earth and twice the radius of Earth. What is the weight of a $100\ kg$ astronaut on this planet compared to their weight on Earth ($W_E$)?

A large tank is filled with water to a depth of $10\ m$. If the density of water is $1000\ kg/m^3$, what is the total mass of water in the tank if the base area is $5\ m^2$?

A solid sphere and a solid cylinder have the same mass and are made of the same material. What is the ratio of the sphere's volume to the cylinder's volume?

An object floats in a liquid. If the whole system is moved to the Moon, where $g$ is smaller, what happens to the submerged fraction of the object's volume?

What happens to a spring if it is stretched beyond its limit of proportionality?

In a tug-of-war, Team A pulls with $500\text{ N}$ to the left and Team B pulls with $500\text{ N}$ to the right. The resultant force is:

A load of $4\text{ N}$ is applied to a spring, and it extends by $2\text{ cm}$. What is the spring constant in $N/cm$?

If the resultant force on an object is zero, the object must be:

An object of mass $4\text{ kg}$ is decelerating at $3\text{ m/s}^2$. What is the magnitude of the resultant force acting on it?

Which of the following would increase the centripetal force acting on a car going around a curve?

When a spring is stretched, it stores energy. This energy is called:

A ball of mass $m$ moves in a horizontal circle of radius $R$ inside a smooth hemispherical bowl. If the ball is at a height $h$ from the bottom, what provides the centripetal force?

A force $F$ stretches a wire by $1.0\text{ mm}$. What force is needed to stretch another wire of the same material but with half the length and half the radius by the same $1.0\text{ mm}$?

A small object of mass $m$ is placed on a rotating horizontal turntable at a distance $r$ from the center. The coefficient of static friction is $\mu$. What is the maximum angular velocity $\omega$ the turntable can have before the object slips?

If a beam is balanced on a pivot, where does the weight of the beam itself act?

A force of $2\ N$ is $50\ cm$ from the pivot. What is the moment in $N \cdot m$?

In Physics, a 'moment' is most closely related to which of these actions?

What is the moment of a $25\ N$ force acting at a perpendicular distance of $4\ m$?

A uniform rod of length $L$ and weight $W$ is balanced on a pivot at one end by a vertical force $F$ at the other end. The relationship between $F$ and $W$ is:

A $30\ cm$ ruler is pivoted at the $15\ cm$ mark. If a $0.5\ N$ weight is at the $5\ cm$ mark and a $0.2\ N$ weight is at the $25\ cm$ mark, which way will it tilt?

Which of these changes would make a stool less stable?

A uniform cylinder of radius $0.1\ m$ and mass $5\ kg$ is resting on a floor. A horizontal force is applied at the very top of the cylinder. What is the maximum force that can be applied without the cylinder toppling if it is prevent from sliding?

A $0.50\ kg$ hammer is used to pull a nail. The distance from the nail to the pivot is $4.0\ cm$ and the distance from the pivot to the hand is $30\ cm$. If a $150\ N$ force is needed to pull the nail, what force must the hand apply perpendicular to the hammer handle?

A uniform beam of weight $W$ is supported by two vertical wires, one at each end. If one wire is moved to the center, what is the tension in the wire that remained at the end?

When a person stands with their feet wide apart, they are more stable because:

For a uniform L-shaped piece of cardboard, the center of gravity is likely to be:

Which change would make a stool less stable?

A gymnast balances on a beam. To stay stable, their center of gravity must remain:

A uniform beam is balanced at its midpoint. If a mass is hung from the left side, what must happen to the pivot to maintain balance without adding more mass?

Which of the following regular shapes has a centre of gravity that does not coincide with its geometric centre if the density is non-uniform?

If you are standing on a bus that suddenly accelerates forward, you tend to fall backward. How does this relate to your centre of gravity?

A uniform cube is balanced on one of its edges on a horizontal surface. This state is called:

A rectangle of sides $10\ cm$ and $20\ cm$ is cut from a large uniform sheet. A circular hole of $5\ cm$ diameter is punched with its center at $(5, 5)$ relative to a corner $(0,0)$. How does the x-coordinate of the CG change?

A uniform solid hemisphere of radius $R$ has its centre of gravity at $3R/8$ from the flat face. If a uniform solid cylinder of radius $R$ and height $R$ is attached to the flat face, where is the CG of the combination from the junction?

Momentum is always conserved in a system that is:

A force of $5\text{ N}$ acts for $10\text{ seconds}$ on an object. The change in momentum is:

The total momentum of two billiard balls before a collision is $5\text{ kg m/s}$. If no external forces act, what is the total momentum after the collision?

In a collision where objects bounce off each other perfectly without losing kinetic energy, the collision is called:

A $0.1\text{ kg}$ ball is dropped and hits the floor at $10\text{ m/s}$. It rebounds at $8\text{ m/s}$. If the contact time was $0.02\text{ s}$, what was the average force?

A $1500\text{ kg}$ car traveling at $15\text{ m/s}$ strikes a wall and stops in $0.15\text{ s}$. What is the average force of the impact?

An object A of mass $2\text{ kg}$ moving at $5\text{ m/s}$ collides with object B of mass $3\text{ kg}$ moving at $2\text{ m/s}$ in the same direction. After collision, A moves at $2\text{ m/s}$. What is the speed of B?

A block of mass $m$ moving at velocity $v$ collides with a spring of constant $k$ attached to a wall. What is the maximum compression of the spring?

An impulse $J$ is applied to a body of mass $m$ initially at rest. The final kinetic energy is:

A particle of mass $M$ moving with velocity $V$ collides with another particle of mass $m$ moving with velocity $v$ in the same direction. If they stick together, what is the loss in kinetic energy?

How much work is done by a $5\text{ N}$ force moving an object $10\text{ m}$?

What is the standard unit of Power?

A toaster converts electrical energy mainly into which form?

Which of the following is a non-renewable source of energy?

An arrow is shot from a bow. The $0.05\text{ kg}$ arrow leaves the bow at $40\text{ m/s}$. How much elastic potential energy was stored in the bow?

A ball is thrown downwards with an initial speed. As it falls through the air, what happens to the sum of its kinetic and gravitational potential energy?

Which of the following is the correct formula for work done?

A small heater is rated at $12\text{ V}$, $3\text{ A}$. It is used to heat $100\text{ g}$ of water. If the heater is $100\%$ efficient and the specific heat capacity of water is $4200\text{ J/(kg}\cdot{}^{\circ}\text{C)}$, how long will it take to raise the temperature of the water by $10\text{ }^{\circ}C$?

A satellite of mass $m$ orbits the Earth in a circular path of radius $r$ at a constant speed $v$. How much work is done by the Earth's gravitational force on the satellite during one complete orbit?

A car uses $0.05\text{ kg}$ of fuel to perform $400\text{ kJ}$ of useful work. If the energy density of the fuel is $40\text{ MJ/kg}$, what is the efficiency of the car's engine?

Which of these is the most likely value for atmospheric pressure at sea level?

A force of $120\ N$ is applied to an area of $0.1\ m^{2}$. What is the pressure in $kPa$?

When drinking through a straw, why does the liquid move up?

What is the effect of increasing gravity on the pressure at the bottom of a liquid column?

If the atmospheric pressure is $1.01 \times 10^5\ Pa$, what is this value in $N/mm^2$?

A block of wood of mass $2\ kg$ has dimensions $0.1\ m \times 0.2\ m \times 0.4\ m$. What is the minimum pressure it can exert on a table? (Take $g = 10\ N/kg$)

Calculate the force exerted by a gas at a pressure of $200\ kPa$ on a circular piston of radius $0.05\ m$. (Use $\pi \approx 3.14$)

A bubble of gas is released from a submarine at a depth of $200\ m$. If the initial pressure is the hydrostatic pressure at that depth and the volume is $V$, at what depth will the volume of the bubble be $2V$? (Assume atmospheric pressure $= 10^5\ Pa$, $\\rho = 1000\ kg/m^3, g = 10\ N/kg$, and constant temperature).

A $500\ N$ girl stands on one stiletto heel. The heel is a circle of radius $0.5\ cm$. What is the pressure she exerts on the floor?

Which of the following would increase the pressure at the bottom of a water tank without changing the depth of the water?