Power is the rate of work done or produced by a system. It will have units of Watts which is equivalent to Joules per second. To determine the work or energy produced by the system, we multiply power with time. We do as follows:
Energy = Power x time
Energy = 1500 J/s (2.0 hr) (3600 s / 1 hr)
Energy = 10800000 J
Centripetal acceleration is the motion inwards towards the center of a circle. It is given by the square of velocity, divided by the radius of the circular path.
ac = v²/r, where ac is the centripetal acceleration in m/s²
Therefore,
Centripetal acceleration = 3²/20m
= 9/20m
= 0.45 m/s²
Thus, the centripetal acceleration is 0.45 m/s²
Answer:
The total normal force acting on the system is approximately 58.8 N
Explanation:
The masses arranged in the stack are;
3 kg, 2 kg, and 1 kg
The mass of the stack system, m = 3 kg + 2 kg + 1 kg = 6 kg
Weight = The force of gravity on an object = m·g
Where;
m = The mass of the object
g = The acceleration due to gravity ≈ 9.8 m/s²
∴ The weight of the stack system, W ≈ 6 kg × 9.8 m/s² ≈ 58.8 N
The direction of the weight force = Perpendicular to the surface (acting downwards)
From Newton's third law of motion, the normal force acts perpendicular to the plane and it is equal in magnitude to the force acting perpendicular to the plane
∴ The magnitude of the total normal force acting on the system = The magnitude of the weight of the system ≈ 58.8 N
The (magnitude of the) total normal force acting on the system ≈ 58.8 N
Answer:
(a). The value of angular speed of the merry-go-round 
= - 5.82 × 
(b). The linear speed of the girl after the rock is thrown V = -1.89 × 
Explanation:
Given data
Mass of the girl 
= 50.6 kg
Mass of merry-go-round 
= 827 kg
Radius r = 3.72 m
The speed of the rock relative to the ground 
= 7.82
(a). The angular speed of the merry-go-round is given by
![\omega = - [\frac{m_{r}v_{r} }{r} ] \frac{2}{m_{m} + 2m_{g} }](https://tex.z-dn.net/?f=%5Comega%20%3D%20-%20%5B%5Cfrac%7Bm_%7Br%7Dv_%7Br%7D%20%20%7D%7Br%7D%20%5D%20%5Cfrac%7B2%7D%7Bm_%7Bm%7D%20%2B%202m_%7Bg%7D%20%7D)
Put all the values in above formula
= - 5.82 ×
This is the value of angular speed of the merry-go-round.
(b). The liner speed of the girl is given by
⇒ V = r ×
⇒ V = - 3.72 × 5.82 ×
⇒ V = -1.89 ×
This is the linear speed of the girl after the rock is thrown.
The correct answer is False.
In fact, electromagnetic waves (which carry energy), do not need a material medium to travel, because they can travel in vacuum as well. So, wave energy can be transmitted also through vacuum.
