Advertisements
Advertisements
Question
A speeding car changes its velocity from 108 kmh−1 to 36 kmh−1 in 4 s. Calculate its deceleration in
- ms−2
- kmh−2.
Advertisements
Solution
Initial velocity = u = 108 kmh−1
u = `108xx5/18` m−1
u = 30 ms−1
Final velocity = v = 36 kmh−1
v = `36xx5/18` ms−1
v = 10 ms−1
Time = t = 4 S
Deceleration = a = `("v"-"u")/"t"`
a = `(10-30)/4`
a = `-20/4` = −5 ms−2
a = `(-5xx3600xx3600)/1000` kmh−2 = −64800 kmh−2
APPEARS IN
RELATED QUESTIONS
Change the speed of 6 m/s into km/h.
In addition to speed, what else should we know to predict the position of a moving body ?
Write the formula for acceleration. Give the meaning of each symbol which occurs in it.
A train starting from Railway Station attains a speed of 21 m/s in one minute. Find its acceleration.
A snail covers a distance of 100 metres in 50 hours. Calculate the average speed of snail in km/h.
A car is moving along a straight road at a steady speed. It travels 150 m in 5 seconds:
What is its average speed ?
Give an example of the motion of a body moving with a constant speed but with a variable velocity. Draw a diagram to represent such a motion.
Draw the shape of the velocity-time graph for a body moving with (a) Uniform velocity and (b) Uniform acceleration.
Define average velocity and give one example.
Write down the type of motion of a body along with the A – O – B of the following distance – time graph.
