Advertisements
Advertisements
प्रश्न
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.
उत्तर
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
संबंधित प्रश्न
A motorcyclist starts from rest and reaches a speed of 6 m/s after travelling with uniform acceleration for 3 s. What is his acceleration ?
An aircraft travelling at 600 km/h accelerates steadily at 10 km/h per second. Taking the speed of sound as 1100 km/h at the aircraft’s altitude, how long will it take to reach the ‘sound barrier’ ?
If a bus travelling at 20 m/s is subjected to a steady deceleration of 5 m/s2, how long will it take to come to rest ?
A car is moving on a straight road with uniform acceleration. The speed of the car varies with time as follows :
Time (s) : 0 2 4 6 8 10
Speed (m/s) : 4 8 12 16 20 24
Draw the speed-time graph by choosing a convenient scale. From this graph :
(1) Calculate the acceleration of the car.
(2) Calculate the distance travelled by the car in 10 seconds.
The speed of a moving object is determined to be 0.06 m/s. This speed is equal to :
Which of the following could not be a unit of speed?
A train takes 2 h to reach station B from station A, and then 3 h to return from station B to station A. The distance between the two stations is 200 km. Find:
The average speed,
The average velocity of the train.
For the motion with uniform velocity , how is the distance travelled related to the time ?
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.
