Answer: <u>Option A: </u>The gas and food are examples of energy.
Explanation:
Work and energy are inter-related. Energy is required to do the work. An equal amount of energy is converted into work. Work and energy have same units. The SI unit is Joule.
The gas and food are sources of energy. They act as fuel. This energy is utilized to perform work. The gas is used to run the car. The food is metabolized inside the body which is a source of energy and utilized to perform every day work.
Hence, The gas and food are examples of energy.
If no frictional work is considered, then the energy of the system (the driver at all positions is conserved.
Let
position 1 = initial height of the diver (h₁), together with the initial velocity (v₁).
position 2 = final height of the diver (h₂) and the final velocity (v₂).
The initial PE = mgh₁ and the initial KE = (1/2)mv₁²
where g = acceleration due to gravity,
m = mass of the diver.
Similarly, the final PE and KE are respectively mgh₂ and (1/2)mv₂².
PE in position 1 is converted into KE due to the loss in height from position 1 to position 2.
Therefore
(KE + PE) ₁ = (KE + PE)₂
Evaluate the given answers.
A) The total mechanical energy of the system increases.
FALSE
B) Potential energy can be converted into kinetic energy but not vice versa.
TRUE
C) (KE + PE)beginning = (KE + PE) end.
TRUE
D) All of the above.
FALSE
Answer:
The two brothers working together will take 7.7 hours to dig the entire ditch.
Explanation:
Assuming T to be the total amount of time taken by both brothers working together, we can say
- 1/T ditch/hour to be the rate at which both brothers dig the ditch together
- 1/14 ditch/hour to be the rate at which the older brother digs the ditch
- 1/17 ditch/hour to be the rate at which the younger brother digs the ditch
So the rate at which both brothers dig the ditch can be calculated by the equation,
1/T = 1/14 + 1/17
T = 238/31 = 7.7 (rounded off to the nearest tenth)
Answer:
none
Explanation:
it's to high up to be affected by the gravity