Uniform Circular Motion

Q. A particle moves along a semicircle of radius $10\text{m}$ in 5 seconds. The magnitude of average velocity of the particle is

1. $4\pi m{s}^{-1}$
2. $2m{s}^{-1}$
3. $4m{s}^{-1}$
4. $2\pi m{s}^{-1}$

Q. In a uniform circular motion, velocity and acceleration are to each other.

1. parallel
2. perpendicular
3. equal

Q.

In a uniform circular motion, ___

1. the motion of an object takes place in a circle at a constant speed

2. the motion of an object takes place in a circle at a constant velocity

3. the motion of an object takes place in a circle with varying speed

4. the motion of an object takes place in a circle at a constant tangential acceleration

Q. A wheel is at rest. Its angular velocity increases uniformly and becomes 60 rad/sec after 5 sec. The total angular displacement is

1. 600 rad
2. 75 rad
3. 300 rad
4. 150 rad

Q. A body is moving in a uniforrm circular motion. It has
acceleration.

1. no
2. an inward radial
3. an outward radial
4. a tangential

Q.

A body moving along a circular path has

1. a constant speed

2. a constant velocity

3. no tangential velocity

4. no radial acceleration

Q.

Calculate the value of the linear velocity of a sphere revolving at a distance of $15cm$ from the axis of rotation, and having an angular speed of $15rad/s$.

1. $0.225m/s$

2. $22.5m/s$

3. $2.25m/s$

4. $0.025m/s$

Q. (1) : If a body moving in a circular path has a constant speed, then there is no force acting on it.
(2) : The direction of the velocity vector of a body moving in a circular path is changing.

1. Both (1) and (2) are true and (2) is the correct explanation of (1)
2. Both (1) and (2) are true but (2) is not the correct explanation of (1)
3. (1) is true but (2) is false
4. (1) is false but (2) is true

Q.

In a popular daredevil trick to complete a vertical loop on a motorcycle, the rider falls off the track because of the less speed before reaching the top of the loop. Determine the minimum speed necessary for a rider to successfully go around a vertical loop of the radius $15meters$.

1. $0.12m/s$

2. $12.12cm/s$

3. $121.2m/s$

4. $12.12m/s$

Q.

If an object is performing a uniform circular motion with a constant angular speed of $20rad/s$. Find the angular displacement in $2sec$.

1. 20 rad

2. 80 rad

3. 40 rad

4. 60 rad

Q. If an object is in uniform circular motion, it has a constant_______ but a changing______.

1. speed; velocity

2. velocity; speed

3. speed; acceleration

4. velocity; acceleration

Q. A body is having a uniform circular motion then, its velocity isand speed is throughout the journey.

1. decreasing
2. constant
3. changing
4. increasing
5. zero

Q. If an object of mass m moves in uniform circular motion, a force F acts on it, whose direction is always towards the centre of the circular path. If F depends on m, speed v of the object, find an expression for F.?

Q.

Which of the following isnt a rectilinear movement?

1. The motion of planes in the sky

2. Kids sliding down from a slide

3. Gravitational forces acting on objects resulting in free fall

4. A car moving in a circular path

Q.

A wheel completes 2000 rotations in covering a distance of 9.5 km. The diameter of the wheel is

1. 1.5 m
2. 1.5 cm
3. 7.5 m
4. 7.5 cm

Q. A wheel completes 2000 rotations in covering a distance of 9.5 km. The diameter of the wheel is

1. $7.5m$
2. $7.5cm$
3. $1.5m$
4. $1.5cm$

Q. ntA car of mass m is moving on a level circular track of radius R.Its coeffecient of static friction between road and tyres of car is represented by (meu)s , the maximum speed of carin circular motion is given byn

Q.

What is the force required for uniform circular motion?

Q.

In a uniform circular motion, acceleration of the object is $80m/s^2$ and the radius is 5 m. Find out the angular speed of the object.

1. 6 rad/s

2. 8 rad/s

3. 2 rad/s

4. 4 rad/s

Q.

Which of the following statement is correct about uniform circular motion?

1. Tangential acceleration is non-zero.

2. Radial acceleration is zero.

3. Acceleration of the body is non-zero.

4. Force acting on the body is zero.

Q.

The driving wheel of a gear system is of radius 1 cm and it has 8 teeth. For twelve rotations of the driving wheel, the driven wheel makes one rotation. Find the radius of the driven wheel.

1. 4 cm

2. 8 cm

3. 12 cm

4. 2 cm

Q. Calculate the angular velocity of the following arms of the clock in rad/sec.

1. $\frac{\pi }{30}$
2. $\frac{\pi }{21600}$
3. $\frac{\pi }{1800}$

Q. A particle moves along two paths $AOB$ and $AB$ of an arc $(r=\pi \text{m})$ as shown in the figure.
What will be the average speed of particle for the paths $AOB$ and $AB$ respectively, if it completes the journey from $A$ to $B$ in $\frac{\pi }{3}\text{sec}$ in each way?

1. $6\text{m/s}$ and $12\text{m/s}$ respectively
2. $2.5\text{m/s}$ and $\frac{\pi }{6}\text{m/s}$ respectively
3. $6\text{m/s}$ and $2\pi \text{m/s}$ respectively.
4. $2\text{m/s}$ and $4.5\text{m/s}$ respectively

Q. A smooth block loosely fits in a circular tube placed on a horizontal surface. The block moves in a uniform circular motion along the tube. Which wall (inner or outer) will exert a non-zero normal contact force on the block?

Q. A wheel completes 2000 rotations in covering a distance of 9.5 km. The diameter of the wheel is

1. 1.5 m
2. 1.5 cm
3. 7.5 m
4. 7.5 cm

Q. The difference between angular speed of minute hand and second hand of a clock is

1. $\frac{59\pi }{900}rad/s^{-1}$
2. $\frac{59\pi }{1800}rad/s^{-1}$
3. $\frac{59\pi }{2400}rad/s^1$
4. $\frac{59\pi }{3600}rad/s^{-1}$