Advertisements
Advertisements
प्रश्न
A train starting from Railway Station attains a speed of 21 m/s in one minute. Find its acceleration.
Advertisements
उत्तर
(b) We will find the value of uniform acceleration.
Initial velocity (u) 0 m/s
Final velocity (v) = 21 m/s
Time taken (t) = 60 s
Acceleration :
`a = (v-u)/t`
Putting the values in the above equation , we get :
`a = (21-0)/60`
= `0.35 "m/s"^2`
APPEARS IN
संबंधित प्रश्न
What is the Differnece between speed and velocity ?
Joseph jogs from one end A to the other end B of a straight 300 m road in 2 minutes 30 seconds and then turns around and jogs 100 m back to point C in another 1 minute. What are Joseph’s average speeds and velocities in jogging?
- from A to B and
- from A to C?
Give an example of motion in which the average speed is not zero but the average velocity is zero.
Express the following in m s-1.
18 km min-1
A car travels the first 30 km with a uniform speed of 60 km h−1 and the next 30 km with a uniform speed of 40 km h−1. Calculate :
- The total time of journey,
- The average speed of the car.
A car accelerates at a rate of 5 m s-2. Find the increase in its velocity in 2 s.
A car is moving in a straight line with speed 18 km h-1. It is stopped in 5 s by applying the brakes. Find:
- the speed of car in m s-1
- the retardation and
- the speed of car after 2 s of applying the brakes.
Figure shows the displacement of a body at different times .
Calculate the velocity of the body as it moves for time interval :
(i) 0 to 5 s,
(ii) 5 s to 7 s
(iii) 7 s to 9 s.

Figure shows the displacement of a body at different times .

Calculate the average velocity during the time interval 5 s to 9 s ,
[Hint : From 5 s to 9 s , displacement = 7 m - 3m = 4m]
A body projected vertically up with a velocity of 10 m/s reaches a height of 20 m. If it is projected with a velocity of 20 m/s, then the maximum height reached by the body is:
