Advertisements
Advertisements
Question
A train travelling at 20 m s-1 accelerates at 0.5 m s-2 for 30 s. How far will it travel in this time ?
Advertisements
Solution
We have to find the distance travelled by the train. We have the following information given,
So, initial velocity, (u) = 20 m/s
Acceleration, (a) = 0.5 m/s2
Time taken, (t) = 30 s
We can calculate the distance travelled by using the 2nd equation of motion,
`s = ut + 1/2at^2`
Put the values in above equation to find the distance travelled by the train,
`(s) = 20(30) + 1/2(0.5)(30)^2`
= (600 + 225) m
= 825 m
APPEARS IN
RELATED QUESTIONS
Give one example of a situation in which a body has a certain average speed but its average velocity is zero.
Define velocity. What is the SI unit of velocity ?
Fill in the following blank with suitable word :
If a body moves with uniform velocity, its acceleration is ..............
Find the initial velocity of a car which is stopped in 10 seconds by applying brakes. The retardation due to brakes is 2.5 m/s2.
A motorcycle moving with a speed of 5 m/s is subjected to an acceleration of 0.2 m/s2. Calculate the speed of the motorcycle after 10 seconds, and the distance travelled in this time.
State how the velocity-time graph can be used to find
The acceleration of a body
A stone thrown vertically upwards takes 3 s to attain maximum height. Calculate
- initial velocity of the stone
- maximum height attained by the stone. (Take g = 9.8 ms−2)
How will the equations of motion for an object moving with a uniform velocity change?
An electron moving with a velocity of 5 × 104 ms−1 enters into a uniform electric field and acquires a uniform acceleration of 104 ms–2 in the direction of its initial motion.
(i) Calculate the time in which the electron would acquire a velocity double of its initial velocity.
(ii) How much distance the electron would cover at this time?
Two stones are thrown vertically upwards simultaneously with their initial velocities u1 and u2 respectively. Prove that the heights reached by them would be in the ratio of `"u"_1^2 : "u"_2^2` (Assume upward acceleration is –g and downward acceleration to be +g)
