Answer:
Centripetal acceleration.
Explanation:
Centripetal acceleration is a property of a body moving in a uniform circular path and it is directed radially towards the center of the circle in which body is rotating.
The force which causes this acceleration is centripetal force which is also directed towards the center of the circle and pulls the body towards its center.
It is calculated through following formula
where v is velocity and r is the radius of the circle.
Answer:
24,187.04 J ≈ 24,200 J
Explanation:
mass (m) = 544 kg
initial speed (u) = 6.75 m/s
final speed (v) = 15.2 m/s
change in height (Δh) = -14 m (negative sign is because there is a decrease in height )
acceleration due to gravity (g) = 9.8 m/s^{2}
How much work was done on the raft by non conservative forces?
work done = change in energy of the system = change in kinetic energy + change in potential energy
work done = () + (mgΔh)
work done = () + (544 x 9.8 x (-14))
work done = 50449.76 - 74,636.8
work done = 24,187.04 J ≈ 24,200 J
Answer: 500 Watts
Explanation:
Power is the speed with which work
is done. Its unit is Watts (
), being
.
Power is mathematically expressed as:
(1)
Where is the time during which work
is performed.
On the other hand, the Work done by a Force
refers to the release of potential energy from a body that is moved by the application of that force to overcome a resistance along a path. It is a scalar magnitude, and its unit in the International System of Units is the Joule (like energy). Therefore, 1 Joule is the work done by a force of 1 Newton when moving an object, in the direction of the force, along 1 meter (
).
When the applied force is constant and the direction of the force and the direction of the movement are parallel, the equation to calculate it is:
(2)
In this case, we have the following data:
So, let's calculate the work done by Peter and then find how much power is involved:
From (2):
(3)
(4)
Substituting (4) in (1):
(5)
Finally: