Question

Suppose that instead of dropping the rock you throw it downwards so that its speed after falling 7 meters is 23.43 m/s. How much kinetic energy did you give the rock in your throw

Answer 1

205.88 ×mass of rock

This problem uses the expression for the kinetic energy of a moving body. K.E = 1/2mv², where m = mass of rock and v = velocity of the rock.

Step-by-step explanation:

We are requested to calculate the kinetic energy but in order to do sk we must first calculate the initial velocity at which the rock was thrown downwards.

Given the following: h = -7m (thrown downwards and assuming upwards to be positive), v = -23.43 (same reason) and g = 9.8m/s².

The full calculation can be found in the attachment below.

Answer 2

3,298.1 Hz

Step-by-step explanation:

Solution is attached