Finding Average Velocity

Q.

A body traveling along a straight line traversed one third of the total distance with a velocity 4 m/s. The remaining part of the distance was covered with a velocity 2 m/s for half of the time and with velocity 4 m/s for the other half of time. The mean velocity averaged over the whole time of motion is

1. 5

2. 4

3. 2

4. 0

Q.

A man walks on a straight road from his home to a market 2.5 km away with a speed of 5 km/h. Finding the market closed, he instantly turns and walks back home with a speed of 7.5 km/h. If the total time of travel is 40 min find the average speed of the man for the whole journey.

1. 

2. 5 km/h

3. 

4. 

Q.

A point moves with uniform acceleration and $v_1,v_2$ and $v_3$ denote the average velocities in the three successive intervals of time $t_1,t_2$ and $t_3$. Which of the following relations is correct?

1. 

2. 

3. 

4. 

Q. The ratio of the numerical values of the average velocity and average speed of a body is always

1. Unity
2. Unity or less
3. Less than unity
4. Unity or more

Q.

A train travels from city A to city B with a constant speed of 10 $m{s}^{-1}$ and return back to city A with a constant speed of 20 $m{s}^{-1}$. Find its average speed during its entire journey.

1. $25m/s$

2. $\frac{40}{3}m/s$

3. $\frac{20}{3}m/s$

4. $20m/s$

Q.

A boy walks to his school at a distance of 6 km with constant speed of 2.5 km/hour and walks back with a constant speed of 4 km/hr. His average speed for round trip expressed in km/hour, is

1. $\frac{24}{13}$

2. $\frac{40}{13}$

3. $3$

4. $\frac{1}{2}$

Q.

If a car covers $2/5^{th}$ of the total distance with $v_1$ speed and $3/5^{th}$ distance with $v_2$ then average speed is

1. $\frac{1}{2}\sqrt{v_1{v}_2}$

2. $\frac{v_1+v_2}{2}$

3. $\frac{2v_1{v}_2}{v_1+v_2}$

4. $\frac{v_1{v}_2}{3v_1+2v_2}$

Q. A car travels 80 km towards north at a speed of 40 km/hr. Then, travels 60 km towards west at a speed of 30 km/hr. Find the magnitude of its average velocity.

1. 35 km/hr
2. 38 km/hr
3. 25 km/hr
4. 20 km/hr

Q. Length of the minute hand in a clock is $10\text{cm}$. Find difference between average speed and magnitude of average velocity (in $cm/min$) of tip of the minute hand from $6$ a.m. to $6:20$ a.m.

1. $\frac{2\pi }{3}-\frac{\sqrt{3}}{2}$
2. $\frac{2\pi }{3}-\frac{1}{2}$
3. $\frac{\pi }{3}-\frac{\sqrt{3}}{2}$
4. $\frac{\pi }{3}-\frac{1}{2}$

Q. A car moving on a straight road covers first $1000\text{s}$ of its journey with speed of $18\text{km/h}$ and next $2000\text{s}$ of its journey with speed of $36\text{km/h}$. Average speed of the car during whole journey is

1. $18\text{km/h}$
2. $36\text{km/h}$
3. $27\text{km/h}$
4. $30\text{km/h}$