Answer:
U = 56877.4 J
Explanation:
The potential energy of a body is that which it possesses because it is located at a certain height above the surface of the earth and can be calculated using the following formula:
U = mgh Formula (1)
Where:
U is the potential energy in Joules (J)
m is the mass of the body in kilograms (kg)
g is the acceleration due to gravity (m/s²)
h is the height at which the body is found from the surface of the earth in meters (m)
Data
m= 81.4 kg
g= 9.8 m/s²
h = 71.3 m
Potential energy of Sean and the parachute at the top of the tower
We replace data in the formula (1)
U = m*g*h
U = (81.4 kg)*(9.8 m/s²)*(71.3 m)
U = 56877.4 N*m
U = 56877.4 J
Answer:
7.6 s
Explanation:
Considering kinematics formula for final velocity as

Where v and u are final and initial velocities, a is acceleration and s is distance moved.
Making v the subject then

Substituting 8.8 m/s for u, 138 m for s and 2.45 m/s2 for a then

Also, v=u+at and making t the subject of the formula

Substituting 27.45 m/s for v, 8.8 m/s for u and 2.45 m/s for a then

Therefore, it needs 7.6 seconds to travel
Answer:
Mechanical waves are waves that require a medium. This means that they have to have some sort of matter to travel through. These waves travel when molecules in the medium collide with each other passing on energy. One example of a mechanical wave is sound.
A 15.75-g<span> piece of iron absorbs 1086.75 </span>joules<span> of </span>heat<span> energy, and its ... </span>How many joules<span> of </span>heat<span> are </span>needed<span> to raise the temperature of 10.0 </span>g<span> of </span>aluminum<span> from 22°C to 55°C, if the specific </span>heat<span> of </span>aluminum<span> is o.90 J/</span>g<span>”C2 .</span>