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2 years ago

What it the weight of an object that is held at a height of 4.5 m above the ground and has 300 j of energy?

1 answer:

Citrus2011 [14]2 years ago

5 0

The energy of an object held at a height of h is equal to its gravitational potential energy, given by
$U=mgh$
where m is the mass of the object, g is the gravitational acceleration and h is the height.

If we re-arrange the formula and we substitute the data of the problem, we can find the weight of the object, mg:
$mg= \frac{U}{h}= \frac{300 J}{4.5 m}=66.7 N$

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A total Δν of 15 km/s is required to achieve an interplanetary mission. The proposed rocket has two stages. The first stage alon

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Answer:

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Explanation:

Given:

A total Δν = 15 km/s

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2 years ago

An object is moving at 2.50 m/s [E]. At a time 3.00 seconds later the object is traveling at 1.50 m/s

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Given parameters:

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Unknown:

The displacement during the first interval = ?

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Velocity = $\frac{Displacement}{Time taken}$

So;

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2 years ago

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Answer:

Part(a): The frequency is $\bf{0.2~Hz}$ .

Part(b): The speed of the wave is $\bf{0.5~m/s}$ .

Explanation:

Given:

The distance between the crests of the wave, $d = 2.5~m$ .

The time required for the wave to laps against the pier, $t = 5.0~s$

The distance between any two crests of a wave is known as the wavelength of the wave. So the wavelength of the wave is $\lambda = 2.5~m$ .

Also, the time required for the wave for each laps is the time period of oscillation and it is given by $T = 5.0~s$ .

Part(a):

The relation between the frequency and time period is given by

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Part(b):

The relation between the velocity of a wave to its frequency is given by

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2 years ago