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2 years ago

Which letter explains why no machine is 100 percent efficient.

Physics

1 answer:

kondaur [170]2 years ago

4 0

Answer:

Explanation:

Think about rubbing your hands together- the friciton produces heat

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A light beam travels through a diamond (n=2.42) to pure water (n=1.33). The refracted ray will:

Marrrta [24]

Answer:

b) bend away from the normal

Explanation:

According to snell's law , if i be the angle of incidence and r be the angle of refraction

sin i / sin r = 1.33 / 2.42

sin i / sin r = .55

Hence sin r > sin i

r > i

In other words angle of refraction will be more than angle of incidence . So, the ray will bend away from the normal .

3 0

3 years ago

It is proposed that a spaceship might be propelled in the solar system by radiation pressure, using a large sail made of foil. W

Anvisha [2.4K]

Answer:

962291.57928 m²

Explanation:

$P_r$ = Pressure = $2\dfrac{I}{c}$ (full reflection)

I = Intensity = $\dfrac{P}{A}=\dfrac{P}{4\pi r^2}$

P = Power = $3.9\times 10^{26}\ W$

c = Speed of light = $3\times 10^8\ m/s$

M = Mass of Sun = $1.99\times 10^{30}\ kg$

m = Mass of ship = 1500 kg

G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²

Force of radiation is given by

$F_r=P_rA\\\Rightarrow F_r=2\dfrac{I}{c}\times A\\\Rightarrow F_r=2\dfrac{P}{4\pi r^2c} A$

This force will balance the gravitational force as stated in the question

$\dfrac{GMm}{r^2}=2\dfrac{P}{4\pi r^2c} A\\\Rightarrow A=\dfrac{4\pi cGMm}{2P}\\\Rightarrow A=\dfrac{4\times \pi\times 3\times 10^8\times 6.67\times 10^{-11}\times 1.99\times 10^{30}\times 1500}{2\times 3.9\times 10^{26}}\\\Rightarrow A=962291.57928\ m^2$

The area of the must be 962291.57928 m²

3 0

3 years ago

Two college teams, A and B, are playing a game of tug of war. Team A applies a force of 103 newtons, but the rope does not move

Kipish [7]

Given that the rope is not moving (acceleration is zero), by the second Law of Newton (F=m*a), the net force acting on the rope is zero.

Then, the force applied by the team B equals the force applied by the tema A: 103 N.

7 0

3 years ago

Read 2 more answers

A plastic box has an initial volume of 2.00 m 3 . It is then submerged below the surface of a liquid and its volume decreases to

nikitadnepr [17]

Answer:

Volume strain is 0.02

Explanation:

Volume strain is defined as the change in volume to the original volume.

It is given that,

Initial volume of the plastic box is 2 m³

It is then submerged below the surface of a liquid and its volume decreases to 1.96 m³