Ask question

Ask question

All categories

3 years ago

7

After a car's engine has been running for a while, if you stand near the car's engine you can often feel heat coming from the en

gine as a result of _____.
A. radiation
B. convection
C. conduction

1 answer:

Orlov [11]3 years ago

4 0

convection i think i think i am wrong

You might be interested in

Which best describes the relationship between humidity and air pressure?

spayn [35]

Answer:<span>Humid air is lighter, so it has lower pressure.

The reason is the molecules of water are H2O, whose molar mass is 18 g/mol.

These molecules displaces molecules of N2 and O2, whose molar masses are:

N2: 2*14g/mol = 28 g/mol, and
O2: 2*16g/mol = 32 g/mol.

Then molecules of 28g/mol and 32 g/mol are being replaced with molecules of 18g/mol, leading to a lower weight of the same volume of air, which results in lower pressure.
</span>

5 0

3 years ago

Read 2 more answers

a student drops an object from the top of a building which is 19.6 m high. How long does it take the object to fall to the groun

zubka84 [21]

Here's a formula that's simple and useful, and if you're really in
high school physics, I'd be surprised if you haven't see it before.
This one is so simple and useful that I'd suggest memorizing it,
so it's always in your toolbox.

This formula tells how far an object travels in how much time,
when it's accelerating:

   Distance = (1/2 acceleration) x (Time²).

   D = 1/2 A T²

For your student who dropped an object out of the window,

   Distance = 19.6 m
   Acceleration = gravity = 9.8 m/s²

D = 1/2 G T²

    19.6 =   4.9   T²

Divide each side by 4.9 :    4 =   T²

Square root each side:    2 =   T

When an object is dropped in Earth gravity,
it takes 2 seconds to fall the first 19.6 meters.

8 0

3 years ago

Read 2 more answers

Help! PROJECTILE PROBLEM: A 7500-kg rocket blasts off vertically from the launch pad with a constant upward acceleration of 2.25

dsp73

Here,

height at failure, h1 = 525 m,
upward acceleration, a = 2.25 m/s^2,
velocity = v m/s,
<span>
SO, </span>
<span>
v^2 = 2*a*h = 2*2.25*525 = 2362.5 </span>
Now, acceleration, g = 9.8 m/s^2,
<span>
SO, </span>
<span>
heigt, h1 = v^2/2g = 2362.5 / 2*9.8 = 120.54 meters </span>
Hence,
<span>
a) </span>
Total height = 525+120.54 = 645.54 meters

b)
<span>time, for h1, t = v/g = sqrt(2362.5)/9.8 = 4.96 sec

---------------------------------

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!</span>

4 0

3 years ago

Read 2 more answers

A tennis player tosses a tennis ball straight up and then catches it after 2.07 s at the same height as the point of release.

prisoha [69]

(a) The ball will accelerate at a speed of 9.81 m/s² while it is in flight.

(b) The ball will be moving at a speed of 0 m/sec when it reaches its highest point.

(c) The ball's initial upward velocity is 20.30 m/s.

(d) It will reach a maximum height of 21.0 m.

<h3 /><h3>What is speed?</h3>

Speed is defined as the change in distance with regard to time. A scalar quantity, speed. It is a temporal element, m/sec is its unit.

The information provided in the issue is;

u is the fall's beginning speed in m/sec;

h is the fall's distance

g is the fall's acceleration or 9.81 m/sec²

a. The ball's speed while in flight is equal to the acceleration caused by gravity, which is 9.81 m/s².

b. When the ball reaches its highest point, its velocity will be zero.

c. The ball's starting velocity is;

v=u-gt

0=u-gt

u=gt

u=9.81 m/s² × 2.07 sec

u=20.30 m/s

d. The formula is used to determine the highest height it can reach.

$\rm u^2 = - 2gh \\\\ (20.30)^2 = -2 \times (-9.8) \times h \\\\ 412.09 = 19.6 \times h\\\\ h = 412.09/19.6\\\\ h = 21.00 m$

As a result, the ball's greatest height, beginning velocity, and acceleration are all 9.81 meters per second, zero meters per second, 20.30 meters per second, and 21 meters accordingly.

To learn more about the velocity, refer to the link: brainly.com/question/862972.

#SPJ1

3 0

2 years ago

WHAT are the highest frequency and the lowest frequency pets of the EM spectrum?

Rus_ich [418]

Highest frequency EM waves: cosmic rays and gama rays

Lowest frequency EM waves:
Radio and Tv waves

8 0

3 years ago