Answer:
54.3N
Explanation:
The normal force is perpendicular to the slope, so:
Normal Force = cos(37.2)(9.8*65).......507.39N
F(friction)=mu*F(normal)
F(friction)=(0.107)(507.39)
F(friction)=54.3N
The bar magnet and the electromagnet act identical. The difference being a electromagnet is a coil of wire that has a power source connect to both ends, this energizes the coil with an electromagnetic field.
Hooke's Law states that the extension is directly proportional to the force applied so:
F/x = constant
F₁/x₁ = F₂/x₂
2 / 0.02 = 1600 / x₂
x₂ = 16 m
Elastic work = 1/2 Fx
= 1/2 * 1600 * 16
= 12.8 kJ
Answer:
C. Increasing its buoyancy
Answer:
Explanation:
The hippopotamus hearing threshold is 100dB
β = 100 dB
The threshold of human hearing is Io = 1 × 10^-12 W/m²
The sound intensity level is given as
β = 10•Log(I / Io)
100 = 10•Log(I / Io)
Divided Both sides by 10
100 / 10 = Log(I / Io)
10 = Log(I / Io)
Take inverse Logarithm ( antilog) of both sides
10^10 = 10^[Log(I / Io)]
10^10 = I / Io
Then,
I = 10^10 × Io
I = 10^10 × 1 × 10^-12
I = 1 × 10^-2 W/m²
I = 0.01 W/m²
The sound intensity is 0.01 W/m²