Well for starters, gravity keeps things down on Earth. Also, gravity applies its force on to cars to maintain stability by forcing the tires to make constant contact to the ground creating friction between the rubber and road surface allowing the car to be moved. I'm sure someone else has better ideas!
Answer:
Magnetic field experienced = 4.5 × 10⁻⁴ T
Explanation:
The magnetic field around an infinite straight current-carrying wire at a distance r from the wire is given by
B = (μ₀I)/(2πr)
B = ?
I = 20 KA = 20000 A
r = 8.9 m
μ₀ = magnetic permeability = 1.257 × 10⁻⁶ T.m/A
B = (1.257 × 10⁻⁶ × 20000)/(2π×8.9) = 4.5 × 10⁻⁴ T
The velocity (V) of a wave is the frequency (F) times the wave length (lambda):
V = F * lamda
lambda is the distance from crest to crest which is twice the distance from crest to trough.
=> lamba = 2 * 3.00 m = 6.00 m
F = number of waves / time = 13.0 waves / 20.2 s
Now you can plug in the values in the formula of V:
V = 6.00 m/wave* 13.0 waves / 20.2 s = 3.86 m/s
Answer: 3.86 m/s
Work is done when spring is extended or compressed. Elastic potential energy is stored in the spring. Provided inelastic deformation has not happened, the work done is equal to the elastic potential energy stored.
