All categories

3 years ago

A _____ is used in car headlights.

Physics

2 answers:

prisoha [69]3 years ago

8 0

Answer:

concave mirror

Explanation:

because it reflects the light so thats why they use it in headlights

uysha [10]3 years ago

7 0

E concave mirror because it reflects the light

You might be interested in

All waves must ____ have to travel through

babunello [35]

<h2>All waves must ____ have to travel through </h2>

Explanation:

Wave

It is the periodic disturbance in a medium.

Types of Wave

There are two types of wave in general depending upon their propagation through a substance.

• Mechanical

• Electromagnetic

Mechanical Wave

It is the kind of wave which needs medium to travel. For example: Sound Wave

That means sound can be heard only whenever there is presence of certain substance like water, glass, air etc .It can’t be heard in vacuum no matter how loud is the sound.

Electromagnetic Wave

Is that which can travel through medium as well as through vacuum. For example: Light

But unlike sound, light can be seen through a substance or in vacuum. That is the reason it is referred as electromagnetic wave.

6 0

2 years ago

A disk of mass M and radius R rotates at angular velocity ω0. Another disk of mass M and radius r is dropped on top of the rotat

AleksandrR [38]

Answer:

$\omega = \frac{(R^2\omega_o}{(R^2 + r^2)}$

Explanation:

As we know that there is no external torque on the system of two disc

then the angular momentum of the system will remains conserved

So we will have

$L_i = L_f$

now we have

$L_i = (\frac{1}{2}MR^2)\omega_o$

also we have

$L_f = (\frac{1}{2}MR^2 + \frac{1}{2}Mr^2)\omega$

now from above equation we have

$(\frac{1}{2}MR^2)\omega_o = (\frac{1}{2}MR^2 + \frac{1}{2}Mr^2)\omega$

now we have

$\omega = \frac{MR^2\omega_o}{(MR^2 + Mr^2)}$

$\omega = \frac{(R^2\omega_o}{(R^2 + r^2)}$

6 0

3 years ago

The ammonia molecule (NH3) has a dipole moment of 5.0×10?30C?m. Ammonia molecules in the gas phase are placed in a uniform elect

Neko [114]

Question (continuation)

(a) What is the change in electric potential energy when the dipole moment of a molecule changes its orientation with respect to E S from parallel to perpendicular?

(b) At what absolute temperature T is the average translational kinetic energy 3/2kT of a molecule equal to the change in potential energy calculated in part (a)?

Answer:

a. 9.0 * 10^-24 Joules

b. 0.44K

Explanation:

Given

Let p = dipole moment = 5.0 * 10^-30 Cm

Let E = Magnitude = 1.8 * 10^6 N/m

The charge in electric potential = Final Charge - Initial Charge

Initial Charge = Potential Energy

Initial Energy = -pE cosФ where Ф = 0

So, initial Energy = - 5.0 * 10^-30 * 1.8 * 10^6

Initial Energy = -9 * 10^-24 Joules

Final Energy = 0

Charge = 0 - (-9.0 * 10^-24)

Charge = 9.0 * 10^-24 Joules

Absolute Temperature

Change in Kinetic Energy = Change in Potential Energy = 9.0 * 10^-24

Change in Kinetic Energy = 3/2kT where k is Steven-Boltzmann constant = 1.38 * 10^-23

So,

9.0 * 10^-24 = 3/2 * 1.38 * 10^-23 * T

T = (9.0 * 10^-24 * 2)/(3 * 1.38 * 10^-23)

T = (18 * 10^-24)/(4.14 * 10^-23)

T = 0.44K

6 0

3 years ago

Energy changes in generator ?

Firdavs [7]

What do you mean? because yes the energy is converted into electricity but the question isn't specific

7 0

3 years ago

Read 2 more answers

Why in drinking hot water, a thin-bottomed glass is taken?

taurus [48]

Answer:

beacause it's contracts

Explanation:

when using a large bottomed glass the hot water cools that's why is good to use thin bottomed glass

6 0

2 years ago