Answer:
Average speed=1.5 m/s
Frequency of pendulum=93.75Hz
Explanation:
We are given
Frequency, 
Average wavelength =
Speed of pendulum, 
Wavelength, 
We have to find the average speed and frequency of pendulum.
We know that
Speed,
Using the formula
Average speed,
Hence, the average speed =1.5m/s
Frequency, 
Using the formula


Hence, the frequency of a pendulum=93.75Hz
Answer:
The electro magnesium of the atoms cause the magnetic force to charge thus creating electricity. just kidding
Explanation:
If you read on the second paragraph it states that magnesium charged created electricity.
Answer:
option C
Explanation:
given,
diameter of circular room = 8 m
rotational velocity of the rider = 45 rev/min
= 
=4.712 rad/s
here in this case normal force is equal to centripetal force
N = m r ω²
N = m x 4 x 4.712²
N = 88.83m
frictional force = μ N
= 88.83m x μ
now, for the body to not to slide
gravity force is equal to frictional force
m g = 88.83 m x μ
g = 88.83 x μ
9.8 = 88.83 x μ
μ = 0.11
hence, the correct answer is option C
Answer : The final energy of the system if the initial energy was 2000 J is, 3500 J
Solution :
(1) The equation used is,

where,
= final internal energy
= initial internal energy
q = heat energy
w = work done
(2) The known variables are, q, w and 
initial internal energy =
= 2000 J
heat energy = q = 1000 J
work done = w = 500 J
(3) Now plug the numbers into the equation, we get

(4) By solving the terms, we get




(5) Therefore, the final energy of the system if the initial energy was 2000 J is, 3500 J