Answer:
Step-by-step explanation:
a) The work done is equivalent to the change in potential energy of the block. The force due to gravity in the direction down the ramp does the work.
ΔPE = mg(Δh) = (1.25 kg)(9.8 m/s²)(1.81 m·sin(55.3°) ≈ 18.23 J
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b) The kinetic energy of the block can be used to estimate the speed:
KE = ΔPE = 1/2mv²
v = √(2KE/m) = √(2(18.23 J)/(1.25 kg)) ≈ 5.4 m/s
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c) Steven has added kinetic energy to the block. So, the final kinetic energy it has will be ...
initial KE + ΔPE = final KE
final KE = (1/2)mv² + 18.23 J = (1/2)(1.25 kg)(2.0 m/s)² + 18.23 J
= 2.5 J + 18.23 J = 20.73 J
So, the final velocity will be ...
v = √(2(20.73)/1.25) ≈ 5.76 m/s
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<em>Comment on the question</em>
For those of you seeking to copy the answer to "which forces do non-zero work?" we observe that there is no list of forces in this question to choose from. The best we can say is that the operative force is the component of gravity that is parallel to the ramp surface.
14.0305 rounded to the nearest hundredth place is 14.03
First, identify the hundredths digit: the 3 in 14.0305
Next, identify if the next digit is greater than 5.
That digit is not greater than or equal to 5 so you would round down.
The greatest common factor is 4.
Answer:
822
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