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2 years ago

Describe a real-world example of the law of conservation of momentum.

1 answer:

4 0

Imagine a car crash. A car coming at a high speed has a head on collision with a car at rest. When the car makes impact, it will move the other car with it at a slower speed then it was travelling at. In this case, the velocity decreased since the car slowed down, but the mass increased since there are now two cars moving. Momentum was conserved because the change in mass accounts for the loss of velocity.

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The tsunami described in the passage produced a very erratic pattern of damage, with some areas seeing very large waves and near

Lunna [17]

Answer:B. The superposition of waves from the primary source and reflected waves produced regions of constructive and destructive interference.

Explanation: Tsunami is described as several waves originating from a water body mainly an ocean caused by Large scale earth movements taking place under the sea.

Superimposition of wave is the movement of one wave on another,it can be constructive or destructive.

Constructive interference is a wave interference that take place causing the Crest of one wave to align with that of another wave leading to high amplitude.

Destructive interference is a wave interference that take place causing the Trouph of one wave to align with the crest of another wave leading to low amplitude wave.

5 0

2 years ago

What is the name of the process that is responsible for the formation of elements heavier than hydrogen? A) fusion B) fission C)

gladu [14]

Answer:

A) Fusion

Explanation:

Fusions of atoms heavier than hydrogen like helium takes place in the core of the star, at the core the temperature and density of gases is the greatest .

5 0

2 years ago

You are walking from your math class to your science class. You are carrying books

kolezko [41]

Answer:

1800J

Explanation:

Given parameters:

Weight of the book = 20N

Total distance covered = 45m + 15m + 30m = 90m

Unknown:

Total work performed on the books = ?

Solution:

To solve this problem we must understand that work done is the force applied to move a body through a certain distance.

So;

Work done = Force x distance

Work done = 20 x 90 = 1800J

8 0

3 years ago

You throw a baseball a distance of 20 meters. Is it work or not work?

OverLord2011 [107]

Yes it is work because when you throw a ball, you transfer energy to it and it moves.

7 0

2 years ago

A ball has a mass of 1.5kg and is thrown straight up with a speed of 60m/s, what is the ball’s momentum:

madam [21]

Answer:

Assumption: the air resistance on this ball is negligible. Take $g = 10\; \rm m \cdot s^{-2}$ .

a. The momentum of the ball would be approximately $60\;\rm kg \cdot m \cdot s^{-1}$ two seconds after it is tossed into the air.

b. The momentum of the ball would be approximately $\rm \left(-45\; \rm kg \cdot m \cdot s^{-1}\right)$ three seconds after it reaches the highest point (assuming that it didn't hit the ground.) This momentum is smaller than zero because it points downwards.

Explanation:

The momentum $p$ of an object is equal its mass $m$ times its velocity $v$ . That is: $\vec{p} = m \cdot \vec{v}$ .

Assume that the air resistance on this ball is negligible. If that's the case, then the ball would accelerate downwards towards the ground at a constant $g \approx -10\; \rm m \cdot s^{-2}$ . In other words, its velocity would become approximately $10\; \rm m \cdot s^{-1}$ more negative every second.

The initial velocity of the ball is $60\; \rm m \cdot s^{-1}$ . After two seconds, its velocity would have become $60\;\rm m \cdot s^{-1} + 2\; \rm s \times \left(-10\;\rm m \cdot s^{-1}\right) = 40\; \rm m \cdot s^{-1}$ . The momentum of the ball at that time would be around $p = m \cdot v \approx 60\; \rm kg \cdot m \cdot s^{-1}$ .

When the ball is at the highest point of its trajectory, the velocity of the ball would be zero. However, the ball would continue to accelerate downwards towards the ground at a constant $g \approx -10\; \rm m \cdot s^{-2}$ . That's how the ball's velocity becomes negative.

After three more seconds, the velocity of the ball would be $0\; \rm m \cdot s^{-1} + 3\; \rm s \times \left(-10\; \rm m \cdot s^{-2}\right) = -30 \; \rm m \cdot s^{-1}$ . Accordingly, the ball's momentum at that moment would be $p = m \cdot v \approx \left(-45\; \rm kg \cdot m \cdot s^{-1}\right)$ .

3 0

3 years ago