Answer:
1500J
Explanation:
Given parameters:
Mass of the block = 30kg
Height = 5m
Unknown:
Gravitational potential energy = ?
Solution:
The Gravitational potential energy of body is due to its position above the ground level.
Gravitational potential energy = mass x acceleration due to gravity x height
So;
Gravitational potential energy = 30 x 9.8 x 5 = 1470J or 1500J
Gravitational force has a major part in the affect of the ball
Answer:
d) The total mechanical energy is constant.
Explanation:
The total mechanical energy of a pendulum is given by:
where
KE is the kinetic energy (the energy of motion), given by
where
m is the mass of the pendulum
v is its speed
PE is the potential energy of the pendulum (the energy due to its position), given by
where
g is the acceleration due to gravity
h is the height of the pendulum relative to the ground
In absence of air resistance, the total mechanical energy of the pendulum is constant. This means that there is a continuous conversion of energy between kinetic and potential. In particular:
- When the pendulum is at its highest position (maximum displacement), the potential energy is maximum while the kinetic energy is minimum)
- When the pendulum crosses its equilibrium position, the kinetic energy is maximum (maximum speed) while the potential energy is minimum