The ultimate energy source for wind comes from Earth's uneven heating on Earth's surface which can be caused mainly by the sun.
Answer:
7,546 J
Explanation:
recall that Potential energy is given by
P.E = mgΔh
where m = 70kg (given)
g = 9.8 m/s² (acceleration due to gravity)
Δh = change in height
= distance from top of building to top of car
= height of building - height of car
= (5+8) - 2
= 11m
substituting all these into the equation:
P.E = mgΔh
= 70 x 9.8 x 11
= 7,546 J
The displacement is 2 m south
Explanation:
Distance and displacement are two different quantities:
- Distance is the total length of the path covered by an object during its motion, regardless of the direction. It is a scalar quantity
- Displacement is a vector connecting the initial position to the final position of motion of an object. The magnitude of the displacement is the distance in a straight line between the two points
For the car in this problem, the motion is:
10 m south
8 m north
Taking north as positive direction, we can describe the two parts of the motion as
![d_1 = -10 m](https://tex.z-dn.net/?f=d_1%20%3D%20-10%20m)
m
Therefore, the final position of the car with respect to the original position is
![x_f = -10 + 8 = -2 m](https://tex.z-dn.net/?f=x_f%20%3D%20-10%20%2B%208%20%3D%20-2%20m)
which means 2 m south: so, the displacement of the car is 2 m south.
Learn more about distance and displacement:
brainly.com/question/3969582
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Answer:
D- component of the gravitational force parallel to the plane increased and normal force exerted by the board decreased
Explanation:
component of the gravitational force parallel to the plane = mg sinθ ; where θ is inclination of the plane . As it increases , sinθ increases and hence component of the gravitational force parallel to the plane increases .
normal force exerted by the board = mg cosθ . As θ increases , cosθ decreases and hence normal force exerted by the board decreases and hence friction force decreases because
Friction force = coefficient of friction x normal force exerted by the board .
coefficient of friction remains constant.