Question

A 55 kg diver falls feeely a 3 m what is her gravitational PE and KE

Answer 1

To calculate the gravitational potential energy (PE) of the diver at a height of 3 m, we can use the equation:

PE = m * g * h

where:
PE is the gravitational potential energy
m is the mass of the diver (55 kg)
g is the acceleration due to gravity (9.8 m/s^2)
h is the height (3 m)

Plugging in the values:

PE = 55 kg * 9.8 m/s^2 * 3 m
PE = 1617 J

So, the gravitational potential energy of the diver at a height of 3 m is 1617 joules.

To calculate the kinetic energy (KE) of the diver, we can use the equation:

KE = (1/2) * m * v^2

where:
KE is the kinetic energy
m is the mass of the diver (55 kg)
v is the velocity

Since the diver is falling freely, we can use the equation for the final velocity (v) as:

v = sqrt(2 * g * h)

Plugging in the values:

v = sqrt(2 * 9.8 m/s^2 * 3 m)
v = sqrt(58.8) m/s
v ≈ 7.68 m/s (rounded to two decimal places)

Now, we can calculate the kinetic energy:

KE = (1/2) * 55 kg * (7.68 m/s)^2
KE ≈ 2030 J (rounded to the nearest whole number)

Therefore, the kinetic energy of the diver is approximately 2030 joules.