Time and Speed

Q.

Abdul while driving to school computes the average speed for his trip to be 20 km/h. On his return trip along the same route there is less traffic and average speed is 30 km/h. What is the average speed for Abduls whole trip?

Q.

A motorcyclist drives from A to B with a uniform speed of $30\raisebox{1ex}{$km$}\!\left/ \!\raisebox{-1ex}{$h$}\right.$ and returns back with a speed of $20\raisebox{1ex}{$km$}\!\left/ \!\raisebox{-1ex}{$h$}\right.$. Find its average speed.

Q.

Distinguish between distance and displacement?

Q.

A car travels 30km at a uniform speed of 40km/h and next 30 km at a uniform speed of 20km/h. find its average speed.

Q.

A car travels 100 km at a speed of 60 km/h and returns with a speed of 40 km/h. Calculate the average speed for the whole journey.

Q.

The distance between Delhi and Agra is 200 km. A train travels the first 100 km at a speed of 50 km/h. How fast must the train travel the next 100 km, so as to average 70 km/h for the whole journey ?

Q.

A train travels the first 15 km at a uniform speed of 30 km/h; the next 75 km at a uniform speed of 50 km/h; and the last 10 km at a uniform speed of 20 km/h. Calculate the average speed for the entire train journey.

Q.

On a 120km/h track , a train travels the first 30km at a uniform speed of 30km/h .how fast must the train travel the next 90 km somas to average 60km/h for the entire trip?

Q.

Under what condition distance and magnitude of displacement is equal?

Q.

A scooterist covers a distance of 3 km in 5 min. Calculate his speed in:

a) cm/s

b) m/s

c) km/h

Q. How to convert 54km/h into m/s

Q.

An electric train is moving with a velocity of 120 km/hr. How much distance will it cover in 30 sec?

Q.

A car covers the first half of the distance in 40 km/hr and the second half in 60 km/hr. what is the avrage speed of the car?

Q.

It takes time 8 min for light to reach from the sun to the earth surface. If speed of light taken to be 3 $\times$ 10${}^8$ ms${}^{-1}$, find the distance from the sun to the earth in km.

Q.

Express $15m{s}^{-1}$ in km$h^{-1}$.

Q.

A train travels 20 km at a uniform speed of 60 km/h and next 20 km at a uniform speed of 80 km/h calculate its average speed.

Q.

A car travels at 54 km/hr for first 20 secs , 36 km/hr for next 30 secs and finally 18 km/hr for next 10 secs. Find its average speed.

Q. A boy runs for 10 minutes at a uniform speed of 9 km/h. At what speed should he run for next 20 minutes so that the average speed comes to 12 km/h.

Q.

A car is moving along a straight road at a steady speed. It travels 150 m in 5 seconds:

(a) What is its average speed?

(b) How far does it travel in 1 second ?

(c) How far does it travel in 6 seconds ?

(d) How long does it take to travel 240 m ?

Q.

The train A travelled a distance of 120km in 3 hr whereas another train B travelled a distance of 180km in 4 hr. Which train travelled faster?

Q.

A car covers 30 km at a uniform speed of 30 km/h. What should be its speed for the next 90 km if the average speed of the entire journey is 60 km/h?

Q. A cyclist goes once a circular track of diameter 105 m in 5 mins. calculate his speed.

Q. Mike is driving his car with an initial velocity of ‘u’ ms${}^{-1}$ and constant acceleration of ‘a’ ms${}^{-2}$. Can we calculate his final velocity after ‘t’ seconds?

Q.

Express each of the following in m/s.

(a) 1 km $h^{-1}$ (b) 18 km $mi{n}^{-1}$

Q.

Why are speed and velocity categorized as scalar and vector quantities, respectively?

Q.

The maximum speed of a train is 90 km/h . It takes 10 hours to cover a distance of 500
km. Find the ratio of its average speed to maximum speed.

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. 11000 km/hr

3. 10890 km/hr

4. 11880 km/hr

Q.

A boy walks from his classroom to the bookshop along a straight corridor towards North. He covers a distance of 20 m is 25 seconds to reach the bookshop. After buying a book, he travels the same distance at the same time to reach back in the classroom. Find (a) average speed, and (b) average velocity, of the boy.

Q.

The distance of a galaxy from the earth is 5.6 $\times$ 10${}^{25}$ m. Assuming the speed of light to be 3 $\times$ 10${}^8$ m S${}^{-1}$ find the time taken by light to travel this distance.

Q.

A car travels from a point A to B at a constant speed of 50 km/h On return journey along the same path it travel at a constant speed of 40 km/h Find its distance and average speed.