Answer:
The correct answer is A. Vibration.
Explanation:
Mechanical waves is formed by the oscillation of matter and therefore transfer energy from one medium to the other. Unlike electromagnetic waves, mechanical waves need some medium to propagate. It requires an initial energy input and thus carries this energy when it propagates. There are three types of mechanical waves namely transverse waves, longitudinal waves and surface waves. Examples of such waves are sound waves, water waves and seismic waves.
Answer:
0.8s
Explanation:
Given parameters:
Height of shelf = 3m
Unknown:
Time it will take to hit the ground = ?
Solution:
To solve this problem, we use the expression below;
x = ut + 
gt²
x is the height
u is the initial velocity = 0m/s
g is the acceleration due to gravity = 9.8m/s²
t is the time taken = ?
Now insert the parameters and solve for t;
3 = (0 x t) +( x 9.8 x t²)
3 = 4.9t²
t² = 0.6
t = 0.8s
Answer:
U = – 0.12J
Explanation:
Given N = 10 turns, I = 5A, r = 5×10-²m
B^ = 0.05 T iˆ+ 0.3 T kˆ
Magnitude of the magnetic field vector B = √(0.05²+0.3²) = 0.304T
Area = πr² = π(5×10-²)² = 7.85×10-³m²
Magnetic moment μ = NIA
μ = 10×5×7.85×10-³ = 0.3925Am²
U = -μ•B = –0.3925×0.304 = –0.12J
The sign is negative because the magnetic moment is aligned with the magnetic field.
