Answer:
The heat energy required is, E = 2200 J
Explanation:
Given,
The mass of paraffin, m = 2 Kg
The energy required to raise the temperature of the paraffin by 200° C = 44000 J
Then the heat energy required to raise the temperature of the paraffin by 10° C is given by,
Since 44000 J raises temperature by 200° C, then
E = 44000 J / 20
= 2200 J
Hence, the energy required to raise the temperature of the paraffin by 10° C is, E = 2200 J
Answer:
Friction force is independent of the direction of the contacting surfaces
Explanation:
It can go any way depending on how much force is being out on it.
Answer:
Regular exercise and physical activity increase muscle strength, bone density, flexibility, and stability. Physical fitness can reduce your risk for and resilience to accidental injuries, especially as you get older.
Answer:
The well is 23.3 m
Explanation:
As the bucket is lifted out of the well, energy in the man is being transferred to the bucket as gravitational potential energy.
Work done against gravity = mass * height * acceleration due to to gravity
W = mgh
5 920 J = 25.9 kg * h * 9.8 m/s²
h = 23.3 m
Answer:
Explanation:
I is the moment of inertia of the pulley, α is the angular acceleration of the pulley and T is the tension in the rope. Let a is the linear acceleration.
The relation between the linear acceleration and the angular acceleration is
a = R α .... (1)
According to the diagram,
T x R = I x α
T x R = I x a / R from equation (1)
T = I x a / R² .... (2)
mg - T = ma .... (3)
Substitute the value of T from equation (2) in equation (3)
T is the acceleration in the system
Substitute the value of a in equation (2)
This is the tension in the string.
