How do we usually hear things? Sound waves are made of ___ that pushes together __

Coin-shaped compartment that contains light-absorbing molecules

Snowcat [4.5K]

Answer:

Coin-shaped compartment that contains light-absorbing molecules - Thylakoid

7 0

3 years ago

If a car skids 66 ft on wet concrete, how fast was it moving when the brakes were applied? (Round your answer to the nearest who

Sonbull [250]

Answer:

If a car skids 66 ft on wet concrete, it will move at 243 ft/s when the brake is applied.

Explanation:

To determine how fast the car was moving, after skidding, the formula below is used:

V = √32*fd

V is the car's speed (ft/s)

d is skid length (ft) = 66 ft

f is the coefficient of friction determined by the material the car was skidding on.

Coefficient of friction for wet concrete is 0.65

V = √32*fd

V = √32 *0.65* 66

V = 242.679 ft/s ≅ 243 ft/s (nearest whole number)

If a car skids 66 ft on wet concrete, it will move at 243 ft/s when the brake is applied.

8 0

4 years ago

Lasers are classified according to the eye-damage danger they pose. Class 2 lasers, including many laser pointers, produce visib

Alexus [3.1K]

Answer:

a) 318.2 W/m^2

b) 2.5 x 10^-4 J

c) 1.55 x 10^-8 v/m

Explanation:

Power of laser P = 1 mW = 1 x 10^-3 W

exposure time t = 250 ms = 250 x 10^-3 s

If beam diameter = 2 mm = 2 x 10^-3 m

then

cross-sectional area of beam A = $\pi d^{2} /4$ = (3.142 x $(2*10^{-3} )^{2}$ )/4

A = 3.142 x 10^-6 m^2

a) Intensity I = P/A

where P is the power of the laser

A is the cros-sectional area of the beam

I = ( 1 x 10^-3)/(3.142 x 10^-6) = 318.2 W/m^2

b) Total energy delivered E = Pt

where P is the power of the beam

t is the exposure time

E = 1 x 10^-3 x 250 x 10^-3 = 2.5 x 10^-4 J

c) The peak electric field is given as

E = $\sqrt{2I/ce_{0} }$

where I is the intensity of the beam

E is the electric field

c is the speed of light = 3 x 10^8 m/s

$e_{0}$ = 8.85 x 10^9 m kg s^-2 A^-2

E = $\sqrt{2*318.2/3*10^8*8.85*10^9}$ = 1.55 x 10^-8 v/m

6 0

4 years ago

In a game of tug of war, team one pulls to the right with a force of 500 newtons and team two pulls to the left with a force of

seraphim [82]

Answer:

Explanation:

There is no set way to do this. All you have to do is define left and right. Left will be minus and right will be the opposite --- plus.

That is completely arbitrary. It could be the other way around. It does not matter.

Left is minus so: - 600 N is the force going left.

Right plus so: + 500 N

Now just add.

Net Force = +500 - 600

Net Force = - 100 N

So the Net Force is - 100 N going to the left.

8 0

3 years ago

Two charges +q and -q are situated at certain distance, at the point exactly midway betwee them what happens on electric field a

Luden [163]

Answer: Electric field is not zero but potential is zero

Explanation:

In science, charge, also recognized as electric charge, electrical charge, or electrostatic charge and expressed q, is a component of a unit of body that reveals the extent to which it has more or fewer electrons than protons.

Considering the direction of the electric field is of positive to negative charge. Therefore, it determination be toward due −q also due to both the charges.

But for potential, it is a scalar quantity, so the sum of potential due to all the charges will be zero.

Henceforth, the option (c) Electric field is not zero but potential is zero is the correct answer.

a incorect

From the above statements, we could conclude that option (c) Electric field is not zero, but potential is zero is the correct answer. So, the option (a) Electric field and potential both are zero is an incorrect solution.

b incorect

Among all the options, the option (c) Electric field is not zero but potential is zero is the correct answer.

Therefore, the option (b) Electric field is zero but potential is not zero is an incorrect solution

d) is incorrect

It has been explained that the option (c) Electric field is not zero but potential is zero is the correct answer.

Hence, the option (d) Electric field is not zero but potential is zero is an incorrect solution.

7 0

3 years ago

How do we usually hear things? Sound waves are made of ___ that pushes together ___.

How do we usually hear things? Sound waves are made of _ that pushes together _.