So, a concave mirror is a mirror that goes inward, thus, making a convex mirror have an outward curvature. Ex: A convex mirror is used at the front of a bus.
Explanation:
F=15000/0.02
=300N
total area contact of the shoes and floor when stood in one foot=0.02m^2/2=0.01m^2
P=F/A
=300/0.01
=30 000Pa/30 000Nm^-2
in another way=15000×2
=30000N/m^2
Answer:
(i) The maximum acceleration upward is 2.02 m/s².
(ii) The maximum acceleration downward is 1.39 m/s².
Explanation:
Let a be the maximum acceleration of the elevator.
The mass of the person at ground is 150 lb. We have to convert the mass into kg,
1 lb = 0.453592 kg
150 lb = 68 kg
170 lb = 77 kg
120 lb = 54 kg
(i) The person experience a force due to Earth's gravity in the downwards direction. The magnitude of this force is:
F₁ = mg = 68 x 9.8 = 666.4 N
The weight of the person decreases as the elevator is moving upwards. So, the force experienced by the person in this case due to gravity is:
F₂ = 54 x 9.8 = 529.2 N
Applying Newton's force equation;
(F₁ - F₂) = ma
(666.4 - 529.2) = 68 x a
a = 2.02 m/s²
(ii) The weight of the person increases as the elevator is moving downwards. So, the force experienced by the person in this case due to gravity is:
F₂ = 77 x 9.8 = 754.6 N
Applying Newton's force equation;
(F₁ - F₂) = ma
(666.4 - 754.6) = 68 x a
a = -1.30 m/s²
The answer is C hope this helps <span />
The answer is D.
C and A are incomplete as they only treat specific types of energy, and B doesn't answer the question.
