Answer:
1470 W
Explanation:
Power: This can be defined as the rate at which work is done or energy is used up. The S.I unit of power is Watt (W).
The expression for power is given as,
P = Energy/time
P = mgh/t ...................... Equation 1
Where P = power, m = mass, h = height, t = time, g = acceleration due to gravity.
Given: m = 75 kg, g =9.8 m/s², h = 1 m, t = 1 s.
Substitute into equation 1
P = (75×1×9.8)/1
P = 735 W.
From the above,
1 hp = 735 W
2 hp = (2×735) W
2 hp = 1470 W.
Hence 2 hp = 1470 W
Answer:
3.735×10⁻⁶ N
Explanation:
From newton' s law of universal gravitation,
F = Gmm'/r² .............................. Equation 1
Where F = Gravitational force between the person and the refrigerator, m = mass of the person, m' = mass of the refrigerator, r = distance between the person and the refrigerator. G = gravitational universal constant.
Given: m = 70 kg, m' = 200 kg, r = 0.5 m
Constant: G = 6.67×10⁻¹¹ Nm²/kg².
F = (6.67×10⁻¹¹×70×200)/0.5²
F = 93380×10⁻¹¹/0.25
F = 373520×10⁻¹¹
F = 3.735×10⁻⁶ N
Hence the force between the person and the refrigerator = 3.735×10⁻⁶ N
We can salve the problem by using the formula:

where F is the force applied, k is the spring constant and x is the stretching of the spring.
From the first situation we can calculate the spring constant, which is given by the ratio between the force applied and the stretching of the spring:

By using the value of the spring constant we calculated in the first step, we can calculate the new stretching of the spring when a force of 33 N is applied:

Answer:

Explanation:
As we know that tension force in the string will be equal to the centripetal force on the string
so we will have

now we have

now we have


now when string length is 0.896 m and its speed is 71.5 m/s then we will have


