I need an explanation, prefer pictures of a note for problem solving. Q6. In you

Question

I need an explanation, prefer pictures of a note for problem solving.

Q6. In your homework, you watched a video of an astronaut dropping a hammer and a
feather on the surface of the moon. The objects hit the ground simultaneously. The point
was
A. That the gravitational force exerted by the moon on both objects was the
same
B. That the weight of objects on all planets is the same
C. That the acceleration due to gravity does not depend on the mass
D. Nature loves vacuum
E. That the hammer and the feather weigh the same on the moon

Q7. If an object moves in a straight line at constant speed, then we can say that
A. That the total force on the object is zero
B. That the acceleration is zero
C. That the linear momentum is changing
D. All of the above statements A thru C are true
E. Some of the above statements A thru C are true

Q8. The top of a playground slide is 3 m off the ground. How much work does a 40 kg
child do in climbing to the top?
A. 1200 J
B. 1200 N
C. 120 N
D. 120 J
E. Depends on the angle of the ladder

Q9. When this child slides to the bottom of the slide, what is the mechanical energy of
the child just before hitting the ground? (Assume that there is no friction on the slide)
A. All kinetic energy, with the same value as the work done in Q13
B. Total energy of the child is zero
C. Half KE and half PE, both with the same value as the work done in Q13
D. Cannot tell unless the velocity of the child is known
E. Depends on how the slide is shaped, due to dependence on the distance
travelled

Q10 Suppose the maximum power that can be a generated by an elevator is 15000Watts.
Can it pull 1000 kg up four floors in 20 seconds? Each floor has a height of 10 m
A. No, because the power required is 100000Watts
B. No, because the power required is 20000Watts
C. Yes, because the power required is 1000Watts
D. Yes because the power required is 10000Watts

E. None of the above

Explanation / Answer

Q6. C

Q7. E

statements A and B are true, while C is false

Q8. A

work done = force X displacement = mass X g X height = 1200 J

Q9. A

At the bottom, all the energy is inetic energy and equal to 1200 J

Q10. E

The power required is 1000 X 10 X 10 / 20 = 5000 W

Related Questions

Navigate

• Browse (All)
• Browse I
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.