Ask question

Ask question

All categories

3 years ago

6

Do you think that rubbing two pieces of woods together would have more or less friction than wood rubbing against smooth metal ?

why?

1 answer:

salantis [7]3 years ago

7 0

Answer: More friction

Explanation: The wood would probably splinter, causing even more friction, while the metal would probably smooth the wood out.

You might be interested in

In the formula V = TR, the "I" means <br>O static charge <br>O current <br>O isotope<br>O immunity

Leokris [45]

Answer:

b is correct answer it I'd correct

8 0

2 years ago

Read 2 more answers

An electron in a television tube is accelerated uniformly from rest to a speed of 8.4\times 10^7~\text{m/s}8.4×10 7 m/s over

stich3 [128]

Answer:

P=3.42×10^-6 J/s

Explanation:

From the kinematics of motion with constant acceleration we know that :

vf^2=vi^2+2*a(xf-xi)

Where :

• vf , vi, are the the final and the initial velocity of the electron

• a is the acceleration of the electron

• xf , xi are the final and the initial position of the electron .

Strategy for solving the problem : at first from the given information we calculate the acceleration of the electron.

Givens: vf = 8.4 x 10^7 m/s , vi, = 0 m/s , xf = 0.025 m and xi = 0 m

vf^2 =vi^2+2*a(xf-xi)

vf^2-vi^2=2*a(xf-xi)

2*a(xf-xi)= vf^2-vi^2

a = (vf^2-vi^2)/2(xf-xi)

Pluging known information to get :

a = (vf^2-vi^2)/2(xf-xi)

= 1.411 × 10^17

From the acceleration and the previous Eq. we can calculate the final velocity of the electron but a new position xf = 0.01 m

so,

vf^2 =vi^2+2*a(xf-xi)

vf^2 =5.312× 10^7

From the following Eq. we can calculate the time elapsed in this motion .

xf =xi+vi*t+1/2*a*t

xf =xi+vi*t+1/2*a*t

t=√2(xf-xi)/a

t=3.765×10^-10 s

now we can use the power P Eq.

P=W/Δt => ΔK/Δt

Where: the work done W change the kinetic energy K of the electron ,

ΔK=Kf-Ki=>1/2*m*vf^2-1/2*m*vi^2

P=1/2*m*vf^2-1/2*m*vi^2/Δt

P=3.42×10^-6 J/s

6 0

3 years ago

Why do radio waves have the lowest frequency of all the waves on the electromagnetic spectrum?

lara [203]

Explanation:

Electromagnetic waves are the waves which are created as the result of the electrical waves which are perpendicular to each other and also perpendicular to the direction of propagation.

Electromagnetic spectrum is range of the frequencies and their respective wavelengths of the various type of the electromagnetic radiation.

In order of the increasing frequency and the photon energy and the decreasing wavelength the spectrum are:

radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays.

The energy of the radio waves photons is the lowest of all the other waves in the electromagnetic spectrum.

Also, $E={h\times \nu}$

Where,

h is Plank's constant having value $6.626\times 10^{-34}\ Js$

Thus, energy is directly proportional to the frequency. The radio waves have the lowest frequency.

8 0

3 years ago

Why are the wheels on a roller coaster hot after a ride. (I know it’s due to friction but I need more of a detailed answer).

telo118 [61]

2 someone's glasses could fall of because of the inertia
roller coaster is in motion but your glasses are opposing and resisting that motion due to inertia....

1 there is a possibility that electrons move from wheels to the rail and vice versa which also means that it is producing some kind of electrical energy

3 question can't answer

8 0

3 years ago

A man attaches a divider to an outdoor faucet so that water flows through a single pipe of radius 9.25 mm into four pipes, each

irinina [24]

Answer:

1.24 m/s

Explanation:

Metric unit conversion:

9.25 mm = 0.00925 m

5 mm = 0.005 m

The volume rate that flow through the single pipe is

$\dot{V} = vA = 1.45 * \pi * 0.00925^2 = 0.00039 m^3/s$

This volume rate should be constant and divided into the 4 narrower pipes, each of them would have a volume rate of

$\dot{V_n} = \dot{V} / 4 = 0.00039 / 4 = 9.74\times10^{-5} m^3/s$

So the flow speed of each of the narrower pipe is:

$v_n = \frac{\dot{V_n}}{A_n} = \frac{\dot{V_n}}{\pi r_n^2}$

$v_n = \frac{9.74\times10^{-5}}{\pi 0.005^2} = 1.24 m/s$

8 0

3 years ago