What is the name of the line drawn perpendicular to the surface where a light ray strikes?

A train is travelling towards the station on a straight track. It is a certain distance from the station when the engineer appli

AleksandrR [38]

Answer:

500 m

Explanation:

t = Time taken

u = Initial velocity = 50 m/s

v = Final velocity = 0

s = Displacement

a = Acceleration = -2.5 m/s²

Equation of motion

$v=u+at\\\Rightarrow 0=50-2.5\times t\\\Rightarrow \frac{-50}{-2.5}=t\\\Rightarrow t=20\ s$

Time taken by the train to stop is 20 seconds

$s=ut+\frac{1}{2}at^2\\\Rightarrow s=50\times 20+\frac{1}{2}\times -2.5\times 20^2\\\Rightarrow s=500\ m$

∴ The engineer applied the brakes 500 m from the station

4 0

3 years ago

The ozone layer is found in which layer of the atmosphere

prohojiy [21]

This question is incomplete because the options are missing; here is the complete question

The ozone layer is found in which layer of the atmosphere?

A. Stratosphere

B. Mesosphere

C. Thermosphere

D. Troposphere

The correct answer is A. Stratosphere

Explanation:

The ozone layer as indicated by its name is mainly composed of Ozone (O2), this layer is essential for life because it filters ultraviolet radiation and acts as a greenhouse effect gas by trapping part of the heat from the sun. Additionally, the ozone layer is located in the stratosphere, which is the second layer of the atmosphere and can be found between 20 km to 50 km from Earth's surface. Moreover, the existence of the ozone layer in the stratosphere makes the temperature increase with height due to the radiation of the sun filter by ozone.

4 0

3 years ago

A thin film of oil of thickness t is floating on water. The oil has index of refraction no = 1.4. There is air above the oil. Wh

kkurt [141]

Answer:

t = 120.5 nm

Explanation:

given,

refractive index of the oil = 1.4

wavelength of the red light = 675 nm

minimum thickness of film = ?

formula used for the constructive interference

$2 n t = (m+\dfrac{1}{2})\lambda$

where n is the refractive index of oil

t is thickness of film

for minimum thickness

m = 0

$2 \times 1.4 \times t = (0+\dfrac{1}{2})\times 675$

$t = \dfrac{0.5\times 675}{2\times 1.4}$

t = 120.5 nm

hence, the thickness of the oil is t = 120.5 nm

7 0

3 years ago

A) Show that the surface temperature of a star can be inferred from measurements of blackbodyfluxes at two different frequencies

Roman55 [17]

Answer:

The answers to the questions have been solved in the attachment.

Explanation:

The answers to part a to e are all contained in the attachment. For answer part b, temperature and frequency were assumed to be fixed or constant. V² is directly proportional to T telling us that variation in T gives us a square in the frequency variation. This tells us why it is difficult when both frequencies are on this side of the black body.

3 0

3 years ago

A rocket blasts off from the Earth's surface. During the initial phase of flight, the engine of the rocket burns fuel at a rate

Katen [24]

Answer:

αβ = Ma

Explanation:

By Newton's 2nd Law, the equation governing the motion of the rocket while the rocket is burning fuel is

αβ = Ma where α = rocket's fuel burning rate, β = relative to the velocity of the rocket, M = instantaneous mass of the rocket and a = acceleration of rocket.

5 0

3 years ago