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3 years ago

Why does a straw look broken viewed in a glass of water?

Physics

1 answer:

Nat2105 [25]3 years ago

7 0

Answer:

This is due to refraction of light

Explanation:

When a straw is placed in a glass it appears to be broken as a result of refraction of light on the air-water interface.

Since, the refractive index of water is more than that of glass.

Also, water is denser than air, which means light travels slower in water than in air.

Most importantly, When light travels from rarer to denser medium it bents towards the normal and deviates from its original path which explains the broken view of straw in a glass of water.

You might be interested in

The vitreous humor, a transparent, gelatinous fluid that fills most of the eyeball, has an index of refraction of 1.34. Visible

Leto [7]

Answer:

a) 298.5 nm , 522.4 nm and b) radiation frequency does not change

Explanation:

When electromagnetic radiation reaches a medium with a different index of refraction, the medium vibrates the molecules, as if it were a resonance process, whereby the medium vibrates at the same frequency as the incident light.

On the other hand, when the light reaches another medium its average speed within the medium changes, it is now less than the speed of light in a vacuum (c) for this to happen as we saw that the frequency is constant there must be a change in the wavelength of the radiation that is characterized by the ratio

λₙ = λ₀ / n

λₙ = 400 nm in the void

λₙ = 400 / 1.34

λₙ= 298.5 nm

λ₀ = 700 nm

λₙ = 700 / 1.34

λₙ = 522.4 nm

The radiation frequency does not change

4 0

2 years ago

A person gives a shopping cart an initial push along a horizontal floor to get it moving, and then lets go. The cart travels for

mash [69]

Answer:

Only a backward force is acting, no forward force.

Explanation:

Once released from the initial push, in absence of friction, the shopping cart would continue moving forward at a constant speed forever.
As it would move at a constant speed, no net force would be acting on it.
So, if it is gradually slowing, there must be a net force producing an acceleration in a direction opposite to the movement.
This force is the kinetic friction force, and is the only force acting on the cart in the horizontal direction.
As any friction force, opposes to the relative movement between the cart and the horizontal floor, which means that is directed backward.
This is consistent with the direction of the acceleration of the cart.

8 0

3 years ago

Why is the motion of an athlete moving along the circular path with Constant speed considered to be an accelerated motion?

Strike441 [17]

The speed is changing its direction all the time. There is an acceleration which changes the direction of the speed – that is called centripetal acceleration. Only uniform linear motions are considered to have no acceleration.

This is the general formula for acceleration

a = dv/dt

When calculating dv, you should keep in mind the change in the velocity vector’s direction. You can easily see in a graph that with dt tending to 0 (so the length of the arc covered is also tending to 0), the difference between vectors Vf and V0 has a direction which is perpendicular to velocity (the shorter the arc, the closest the angle is to 90 degrees).

There is a formula (which can be deducted from the previous formula) which allows you to calculate the acceleration:

a = v^2/r

Let’s talk about the units:

v is in m/s

r is in m

so v^2/r

is in (m/s)^2/m = (m^2/s^2)/m = m/s^2

which is the same unit as dv/dt:

dv/dt = (m/s)/s= m/s^2

5 0

3 years ago

Hans Langseth's beard measured 5.33 m in 1927. Consider two charges, q1 = 2.42 nC and an unspecified charge, q2, are separated 5

schepotkina [342]

Answer:

-7.89 * 10^(-9) C

Explanation:

Parameters given:

q1 = 2.42 nC = 2.42 * 10^(-9) C

Distance between q1 and q2 = 5.33 m

q3 = 1.0 nC = 1 * 10^(-9) C

Distance between q1 and q3 = 1.9 m

Distance between q2 and q3 = 5.33 - 1.9 = 3.43 m

The net force acting on q3 is:

F = F(q1, q3) + F(q2, q3)

F = (k*q1*q3)/1.9² + (k*q2*q3)/3.43²

F = (9 * 10^(9) * 2.42 * 10^(-9) * 1 * 10^(-9))/3.61 + (9 * 10^(9) * q2 * 1 * 10^(-9))/11.7649

F = 6.033 * 10^(-9) + 0.765*q2

If the net force is zero:

0 = 6.033 * 10^(-9) + 0.765*q2

-0.765*q2 = 6.033 * 10^(-9)

=> q2 = -[6.033 * 10^(-9)]/0.765

q2 = -7.89 * 10^(-9) C

3 0

2 years ago

Why is gravitational force and gravity not the same thing?

vekshin1

Answer:

gravitational force is a force while gravity is a fundamental quantity

Explanation:

3 0

2 years ago

Read 2 more answers