Answer:
The answer is B) Magnetic field
Explanation:
I chose it and I got it right
Answer: 9130 joules
Explanation:
Workdone by wheelbarrow = ?
Time = 11 seconds
Power = 830 watts
Recall that power is the rate of doing work. Thus, power is workdone divided by time taken.
i.e Power = (workdone/time)
830 watts = Workdone / 11 seconds
Workdone = 830 watts x 11 seconds
Workdone = 9130 joules
Thus, 9130 joules of work is required to get the wheelbarrow across the yard.
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:
A, B, and E
Explanation:
The springs are identical, and are compressed the same amount, so they have the same initial elastic potential energy. (E is true)
Energy is conserved, so the darts have the same amount of kinetic energy. (A is true, C is false)
The lighter dart has the same energy as the heavier dart. Since it has less mass, it must have a greater speed. (B is true, D is false)
Answer:
-5.1 kg m/s
Explanation:
Impulse is the change in momentum.
Change in momentum= final momentum - initial momentum=m
+m
Plugging in the values= -0.15*24 - (0.15*10) (The motion towards the pitcher is negative as the initial motion is considered to be positive)
Impulse=-5.1 kg m/s (-ve means that it is the impulse towards the pitcher)