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3 years ago

SOMEONE PLEASE HELP!!

Physics

1 answer:

Arisa [49]3 years ago

7 0

Hello!

$\large\boxed{\text{C. 7,350,000 J}}$

Use the equation:

$PE = mgh$

Where:

m = mass of the object (kg)

g = acceleration due to gravity (≈9.8 m/s)

h = height above ground (m)

Plug the given values into the equation:

PE = 7500 · 9.8 · 100

PE = 7,350,000 Joules.

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Answer:

b. -11.6 cm

Explanation:

We have given parameters:

Length, l = 1.5 m = 150 cm

Mass of weight, $m_1$ = 20 kg

Width, x = 4 cm

Distance d = 4 cm

Mass of bar, $m_{bar}$ = 5 kg

We are asked to find the center of mass from the mid-point, $X_{CM} = ?$

Since 3 weights are on the left and 2 weights are on the right, we know:

$m_{left}$ = 3 * 20 = 60 kg

$m_{right}$ = 2 * 20 = 40 kg

And also we know that, $M = \frac{l}{2}$ = 150/2 = 75 cm

For the left side, center of mass is:

$x_{left} = \frac{3 * 4}{2} = 6$ cm

From the midpoint, the distance to the left is:

$X_{left} = -(M - 4 - x_{left}) = -(75 - 4 -6) = -65$ cm

For the right side, center of mass is:

$x_{right} = \frac{2 * 4}{2} = 4$ cm

From the midpoint, the distance to the right will be:

$X_{right} = (M - 4 - x_{right}) = (75 - 4 - 4) = 67$ cm

Hence,

$X_{CM} = \frac{m_{right}*x_{right} + m_{left}*x_{left} }{m_{right} + m_{left} + m_{bar}} = \frac{40 * 67 - 60 * 65}{40 + 60 + 5} = -11.62$ cm

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3 years ago

What kind of energy does an unlit match have?

Rudiy27

It’s is none of the above answers.
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During the last shot of the game, the basketball goes from rest to 15 m/s and reaches the backboard in 0.41 s. What was the acce

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Answer:

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In order to climb, you need to work against work done by gravity on the pack.

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So you need to do 2100 joules of work to lift your pack.

Power is the rate of work done.

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Explanation:

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3 years ago

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Newly discovered planet has twice the mass and three times the radius of the earth. What is the free-fall acceleration at its su

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Answer:

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Explanation:

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On new planet

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Dividing the two equations we get

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Answer:

The fireman will continue to descend, but with a constant speed.

Explanation:

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We need to understand the difference between static friction and kinetic friction.

Static friction occurs in objects that are stationary, while kinetic friction occurs in objects that are already in motion.

In static friction, when the frictional force matches the weight or normal force of the object, the object remains stationary.

While in kinetic friction, when the frictional force matches the normal force, the object will stop accelerating. This is the case of the fireman sliding down the pole as discussed above.

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