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AleksandrR [38]
4 years ago
6

A 10-kg sled carrying a 30-kg child glides on a horizontal, frictionless surface at a speed of 6.0 m/s toward the east. The chil

d jumps off the back of the sled, propelling it forward at 20 m/s. What was the child’s velocity in the horizontal direction relative to the ground at the instant she left the sled?

Physics
1 answer:
raketka [301]4 years ago
3 0

Answer:

- 1.33m/s

Explanation:

We choose the system to be the child and the sled. The surface is friction less, which means that there are no forces exerted on the system horizontally. This means that the horizontal momentum component of the system is constant and conserved.

So we can use the conservation momentum principle to find the velocity of the child just after he leaves the sled.

This is shown in the attached file.

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Answer:

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Rearrange \begin{aligned}(\text{net force}) &= (\text{normal force}) - (\text{weight})\end{aligned} to obtain an expression for the magnitude of the normal force on this astronaut:

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3 0
2 years ago
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1. a. increase

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E = -ΔV/Δs

As this equation indicates that the electric field is due to the change in potential and change in the the position of charge. Electric field is directed towards the decreasing potential and the electron moves in the opposite direction of the electric field  where potential increases. Thats why the best explanation is that the electron has a negative charge it moves towards the positive region where the electric potential energy increases.

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彼が好きな男のような話は妻と関係があったのでそう

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lol okay

from: a random person :)

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