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1 year ago

A train slows from 60m/s to 20m/s in 50s

Physics

2 answers:

Dovator [93]1 year ago

7 0

Answer:

a = -4/5 m/s^2

Explanation:

Acceleration = change in velocity / time

change in velocity = final velocity - initial velocity

a = (20 m/s - 60 m/s) / 50 s

a = -40 m/s / 50 s

a = -4/5 m/s^2

hope this helps! <3

Alexeev081 [22]1 year ago

4 0

Answer:

- 4/5 m/s^2

Explanation:

It is going from 60 to 20 m/s so ACCELERATION is negative

acceleration = change in velocity / time

= -40 m/s / 50 s = - 4/5 m/s^2

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3 years ago

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$\Large{\red{\bf{\blue{\dag} Answer:-}}}$

Newton's First Law of Motion :

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More to know :-

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Newton's First Law of Motion :-

It states that an object stays in rest or in uniform motion unless and until compelled by an external unbalanced force . This is also known as " Law of Inertia " .

Ex - (i) We tend to fall backwards while standing in the bus , when it starts suddenly.

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3 years ago

A football player runs from his own goal line to the opposing team's goal line, returning to his forty-yard line, all in 22.4 s.

Bumek [7]

I assume L=120 yards as the length of the football field.

1) The average speed is given by the total distance covered by the player divided by the time taken.
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$S=120y+(120-40)y=120y+80y=200 y$
And the time taken is t=22.4 s, so the average speed of the player is
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2) The find the average velocity, we should also consider the direction (and the sign) of the velocity.
In the the first part of the motion, the player goes from one goal line to the other one, so he covers 120 y. However, in the second part of the motion he goes back by 80 y. Therefore, the net displacement of the player is
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3 years ago