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Levi and Clara are trying to move a very heavy box. Levi is pushing the box with a force of 30 N, and Clara is pulling the box with a force of 50 N. The box exerts a frictional force of 65 N.

User Paroxyzm
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2 Answers

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Answer:

The answer is B. There is a net force of 15 N allowing Levi and Clara to move the box.

Step-by-step explanation:

If you're taking the Lesson 11: Motion & Forces Unit Review the answers are:

1. D. 325 kg · m/s

2. C. It is always the same as it was before the collision

3. C. It increases the time it takes for the person to stop

4. C. a 75kg dining table

5. B. The mass of the rocket decreases as fuel is burned, so the acceleration increases.

6. C. An increase in the distance between the objects causes a greater change in the gravitational force than the same increase in mass.

7. D. The hammer hits the ground before the feather on Earth, and the hammer and feather hit at the same time on the moon.

8. C. C

9. C. Surface 1 is blacktop, Surface 2 is gravel, and Surface 3 is ice.

10. B. using shaving cream, rather than shaving on dry skin

11. A. a vector with magnitude and direction

12. B. 10 N

13. B. There is a net force of 15 N allowing Levi and Clara to move the box.

14. D. Finley → Xander → Max

15. C. Carla slowed down in the beginning of her trip, stopped, and then sped up.

16. A. positive

17. B. His speed was 2 m/s, and his velocity was 0.

18. B. His speed was 2 m/s, and his velocity was 0.

19. A. the ocean surface

20. A. Atlanta

21. B. W

22. A. measurement and direction

**17 & 18 are the same question on the review

I just took the review so these are 100% correct :) (btw these are for Connexus... so yeah but I'm pretty sure they're all the same)

hope this helps :)

User Dumdum
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The net force on the box is:
50 + 30 - 65
= 15 Newtons
This can be used in conjunction with
F = ma
to calculate the acceleration of the box if its mass is known.
User Mrog
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