If an object is related from top of 200m high building find its velocity and time when it hits the ground.(g=(10m/s^2)

The velocity at the ground is 63.25 m/s and time taken is 6.325 s.

Explanation:

Given:

As the object is released, the initial velocity is,

Displacement of the object is,

To find:

Velocity at the bottom,

Time to reach the bottom,

The acceleration of the object is due to gravity and hence equal to

Now, using the following equation of motion:

Now, using the equation of motion relating time and velocity:

Therefore, the velocity at the ground is 63.25 m/s and time taken is 6.325 s.

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle