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Westkost [7]
3 years ago
9

A force of 70 N is applied to a 28 kg rock causing it to slow down from 25 m/s to 15 m/s, a change in velocity of 10 m/s. How lo

ng was that force applied?
Physics
1 answer:
maksim [4K]3 years ago
7 0

Answer: 4 s

Explanation:

Given

The applied force is 70 N

mass of the rock is 28 kg

initial velocity u=25\ m/s

final velocity v=15\ m/s

Deceleration provided by force is

a=-\dfrac{70}{28}=-2.5\ m/s^2

using the equation of motion

v=u+at\\\Rightarrow 15=25-2.5t\\\Rightarrow 2.5t=10\\\Rightarrow t=4\ s

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al aplicar una fuerza de 2 N sobre un muelle este se alarga 4cm.¿cuanto se alargara si la fuerza es el triple?¿que fuerza tendri
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1) 12 cm

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Explanation:

1)

The relationship between force and elongation in a spring is given by Hooke's law:

F=kx

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F=2 N

x=4 cm

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2)

In this second problem, we know that the elongation of the spring now is

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F=(0.5)(6)=3 N

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6 0
3 years ago
a student measure the mass of an 8 cm^3 block of brown sugar to be 12.9 g. what is the density of the brown sugar?
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3 years ago
What is the total displacement???
muminat
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Here, v(0)=10, v(25)=34 (approx.)
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g100num [7]

Answer:

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