Question
A body is thrown vertically up from the ground with an initial speed u and it reaches the maximum height h at time t0.
What is the height it reaches at ½ t0?
Answer
We first define the upwards direction as positive.
When the body reaches the maximum height, the speed of the body is 0.
Knowing this, we can find expressions for h and t0. The acceleration of the body is taken to be 10 ms-2 downwards. Since we define upwards to be positive, the acceleleration will be -10 ms-2.
When the time is ½ t0,
Now that we know the speed at ½ t0, we can find the height travelled by the body.