Answer:
(a)
(b) 
Explanation:
Part (a)
The total length of copper cord L=86.3 m
The cross sectional area A=1.71×10⁻⁶m²
The resistivity of copper p=1.72×10⁻⁸Ω
Thus the resistance of extension cord is

Part (b)
The resistance of trimmer Rt=17.9 ohms
When voltage of 120V is applied then the current I is passing through series circuit is

Thus the voltage across the trimmer is:

Answer:
A) K / K₀ = 4 b) v / v₀ = 4
Explanation:
A) For this exercise we can use the conservation of mechanical energy
in the problem it indicates that the displacement was doubled (x = 2xo)
starting point. At the position of maximum displacement
Em₀ = Ke = ½ k (2x₀)²
final point. In the equilibrium position
= K = ½ m v²
Em₀ = Em_{f}
½ k 4 x₀² = K
(½ K x₀²) = K₀
K = 4 K₀
K / K₀ = 4
B) the speed value
½ k 4 x₀² = ½ m v²
v = 4 (k / m) x₀
if we call
v₀ = k / m x₀
v = 4 v₀
v / v₀ = 4
I think centripetal force ☺
9.8 ms^-2 is acceleration
Answer:
Mass of car = 1098 kg
Explanation:
Here law of conservation of momentum is applied.
Let mass of car be m.
Initial momentum = Final momentum.
Initial momentum = 4350 x 7.39 + m x 0 = 32416.5 kgm/s
Final momentum = 4350 x 4.55 + m x 11.5 = 19792.5+11.5m
We have
19792.5+11.5m = 32416.5
m = 1097.97 kg
Mass of car = 1098 kg