The power of a machine depend on two factors are work and time.
Option C
<u>Explanation:</u>
In science, power defined as the amount of work done in a unit time. i.e. delivering work in a rate of time or energy supply, expressed in input of work or transmitted energy divided by the time interval (t) or W/t.
Example: Some work can be done in the long run with a low-power engine or in a short time with a motor with high performance. The equation for power can be given as
Answer:
9 N
Explanation: Given that L = side of the cube = 10cm = 0.1m
Mass = Density * Volume
Let’s determine the volume of the cube in m^3.
V = L^3
V = 0.1^3 = 0.001m^3
Mass = 0.001 * 2.053 * 10^4 = 20.53kg
Weight = 20.53 * 9.8 = 201.194
Buoyant force = 201.194 – 192 = 9.194 N
This is approximately 9 N.
Answer:
Explanation:
We shall apply concept of Doppler's effect of apparent frequency to this problem . Here observer is moving sometimes towards and sometimes away from the source . When observer moves towards the source , apparent frequency is more than real frequency and when the observer moves away from the source , apparent frequency is less than real frequency . The apparent frequency depends upon velocity of observer . The formula for apparent frequency when observer is going away is as follows .
f = f₀ ( V - v₀ ) / V , f is apparent , f₀ is real frequency , V is velocity of sound and v is velocity of observer .
f will be lowest when v₀ is highest .
velocity of observer is highest when he is at the equilibrium position or at middle point .
So apparent frequency is lowest when observer is at the middle point and going away from the source while swinging to and from before the source of sound .
Answer: 2352 J
Explanation:
A body's<u> gravitational potential energy</u> 
depends on its position and is mathematically expressed as follows:
Where:
is the mass of the skater
is the acceleration due gravity
is the skater's current height
Solving:
