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3 years ago

A hooligan throws a stone vertically down with an initial speed of 17 m/s from the roof of a building 51 metres above the

Physics

1 answer:

pshichka [43]3 years ago

4 0

Answer:

Explanation:

impact velocity is

√(18² + 2(-9.8)-51) = 36 m/s

average velocity is (17 + 36)/2 = 26.5 m/s

t = d/v = 51 / 26.5 = 1.9 s

if ground is origin and UP positive

0 = 51 - 17t - ½(9.8)t²

quadratic formula

t = (17 ±√(17² - 4(-4.9)(51))) / (2(-4.9))

t = (17 ± 36) / -9.8

t = - 5.4 s which we ignore as the stone is not thrown yet

t = 19 s

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Answer:

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Delilah does 170 Joules of work in 30 seconds. Adam does 260 Joules of work in 20 seconds. Who was more powerful?

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3 years ago

A person sitting on a pier observes incoming waves that have a sinusoidal form with a distance of 2.5 m between the crests. Of a

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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, $d = 2.5~m$ .

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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):

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Part(b):

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3 years ago

A point charge q1 is held stationary at the origin. A second charge q2 is placed at point a, and the electric potential energy o

Brrunno [24]

The electric potential energy of the pair of charges when the second charge is at point b is 7.3 x 10⁻⁸ J.

<h3>Electric potential energy</h3>

When work is done on a positive test charge to move it from one location to another, potential energy increases and electric potential increases.

The electric potential energy between the charges when the second charge is at point b is calculated as follows;

ΔU = -w

Ui - Uf = w

Uf = Ui - w

where;

Uf is the final potential energy

Ui is the initial potential energy

w is the work done by the force

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Uf = 5.4 x 10⁻⁸ J + 1.9 x 10⁻⁸ J

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Thus, the electric potential energy of the pair of charges when the second charge is at point b is 7.3 x 10⁻⁸ J.

Learn more about electric potential energy here: brainly.com/question/14306881

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2 years ago