Answer:
B) 100 J
Explanation:
Assuming the distance given is measured along the incline, the vertical change in height is (5 m)(sin 30°) = 2.5 m. Then the change in potential energy is ...
∆PE = mg(∆h) = (4 kg)(10 m/s^2)(2.5 m) = 100 J
Answer:
7.04 m
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity = 0
s = Displacement on Earth = 1.2 m
a = Acceleration due to gravity on Moon = 1.67 m/s²
a = Acceleration due to gravity Earth= 9.81 m/s²
Accelration going up is considered as negetive
Initial Velocity of the ball
Assuming that the ball is thrown with the same velocity on the Moon, displacement of the ball is
The displacement of the ball on the moon is 7.04 m
Answer:
Explanation:
No.
There is a difference between energy, called heat in this case, and temperature, which is a measure of the amount of heat contained in a material and is dependent on the material properties.
Temperature difference is what causes heat to move from one body to another.
Two objects at different temperatures placed in contact with one another will cause heat to move from the warmer body to the colder body until the temperature difference is eliminated.
The amount of heat leaving the warmer body will exactly equal the amount of heat absorbed by the cooler body. (assuming isolated system of two bodies) The temperature change within each of those bodies could be vastly different.
Example would be a 2 mm bead of molten lead dropped into a liter glass of tap water. The lead may cool several hundred °C as it solidifies while the water temperature would increase less than 1 °C
Answer: 87500J
Explanation:
Given that,
Power exerted by crane = 3,500 W
Time taken = 25 seconds
work done by crane = ?
Since power is the rate of work done per unit time, then power is workdone by the crane divided by the time taken.
i.e power = work / time
3,500 W = work / 25 seconds
Work = 3500W x 25 seconds
Work = 87500J
Thus, 87500 joules of work was done by the crane.
Answer:
686.7N
Explanation:
Given data
Mass= 70kg
We know that the buoyant force experienced by the person is equal to the weight of the person
Hence the weight is
Weight = mass* Acceleration
Weight= 70*9.81
Weight= 686.7N
Therefore the weight is 686.7N
