Average Speed

Q.

An auto travels with a uniform speed u for the first half duration and the next half duration with a uniform speed v. Find its average speed.

1. 

2. 

3. 2uv

4. uv

Q. By walking at $\frac{3}{4}th$ of his usual speed, a man reaches office 20 minutes later than usual. What is his usual time?

1. 30 minutes
2. 60 minutes
3. 50 minutes
4. 70 minutes

Q.

It was a rainy day in Bangalore. Rohit was sitting besides the window when he saw a lightning. He started his stop watch. He found that after $22$ seconds of lightning its roaring was heard. Calculate the height of the clouds which caused this lightning. Given, speed of light = $3\times {10}^8$ $m{s}^{-1}$ and speed of sound = $340m{s}^{-1}$.

1. $8.5km$
2. $10km$
3. $7.5km$
4. $5km$

Q. Sohail cycles on a circular track in anticlockwise direction as shown in figure. He travels with a speed ‘V’ to cover the path AB, next with speed ‘2V’ from B to C and with a speed of ‘3V’ from C to A. What is his average speed for the total journey?

1. 2V
2. 6V
3. 3V
4. $\frac{V}{2}$

Q.

A particle is moving from point A to point B and covers the entire distance of 10 km in just 2 minutes. What would be the speed at which the particle was traveling?

1. $53.3m{s}^{-1}$

2. $83.3m{s}^{-1}$

3. $90.3m{s}^{-1}$

4. $80.3m{s}^{-1}$

Q. An insect moves along the sides of a wall of dimension $12m\times 5m$, starting from one corner and reaches the diagonally opposite corner. If the insect takes $2s$ for its motion, then find the ratio of average speed to average velocity of insect.

1. $13:5$
2. $17:12$
3. $12:5$
4. $17:13$

Q. An object travels at $50m{s}^{-1}$ for the first 2 seconds and travels at $70m{s}^{-1}$ for the next 2 seconds. What is its average speed for the first 4 seconds?

1. $50m{s}^{-1}$
2. $56m{s}^{-1}$
3. $70m{s}^{-1}$
4. $60m{s}^{-1}$

Q.

Time is a __ quantity?

Q. If the speed of a body is constant then it

1. might be accelerated
2. must be accelerated
3. has a constant velocity
4. cannot be accelerated

Q.

A satellite is orbiting earth at a distance of 42000 km in a circular orbit. It completes one revolution in 24 hours. Calculate its linear speed.

1. 10990 km/hr

2. 10890 km/hr

3. 11000 km/hr

4. 11880 km/hr