It can be a solid, liquid, gas,plasma,etc. When waves travel through a medium, the particles of the medium are not carried along with the wave.For example, water waves have to travel in water. Sound waves need a solid, a liquid or a gas to travel in.

8 0

3 years ago

Read 2 more answers

While pulling a bicycle out of the garage, you must pull it a total of 1.7 m with a force of 27 n. how much work are you doing o

Solnce55 [7]

Work = force in the direction of the movement x distance = 27 N x 1.7 m

Work = 45.9 joules

Answer: option c.

8 0

3 years ago

Read 2 more answers

Use the work-energy theorem to determine the force required to stop a 1000 kg car moving at a speed of 20.0 m/s if there is a di

Vlad1618 [11]

Answer:

4.44 kN in the opposite direction of acceleration.

Explanation:

Given that, the initial speed of the car is, $u=20m/s$

And the mass of the car is, $m=1000 kg$

The total distance covered by the car before stop, $s=45m$

And the final speed of the car is, $u=0m/s$

Now initial kinetic energy is,

$KE_{i}=\frac{1}{2}mu^{2}$

Substitute the value of u and m in the above equation, we get

$KE_{i}=\frac{1}{2}(1000kg)\times (20)^{2}\\KE_{i}=20000J$

Now final kinetic energy is,

$KE_{f}=\frac{1}{2}mv^{2}$

Substitute the value of v and m in the above equation, we get

$KE_{f}=\frac{1}{2}(1000kg)\times (0)^{2}\\KE_{i}=0J$

Now applying work energy theorem.

Work done= change in kinetic energy

Therefore,

$F.S=KE_{f}-KE_{i}\\F\times 45=(0-200000)J\\F=\frac{-200000J}{45}\\ F=-4444.44N\\F=-4.44kN$

Here, the force is negative because the force and acceleration in the opposite direction.

6 0

3 years ago

How long does it take the moon to go through an entire set of phases?.

Bas_tet [7]

It take approximately 29.5 days for moon to do its entire set of phases.

<h3>Explanation</h3>

The Moon is the only natural satellite of the Earth which undergoes three motions, that is :

Rotating on its own axis
Evolving around the Earth
Together with the Earth evolving around the sun as the center of the solar system

With that, the moon has two periods of revolution, namely:

Sidereal revolution, which is the original revolution of the Moon. This sidereal revolution is really the time it takes the Moon to orbit the Earth. The sidereal revolution of the moon has a time span of 27.3 days or more accurate is approximately 27 days, 7.72 hours.
Synodic revolution, namely the revolution of the Moon as seen from Earth as a series of moon phases (from the new moon phase, to the next new moon phase). The synodic revolution is slower, because the Moon needs to catch up with the Earth rotating in the same direction as the Moon. The synodic revolution of the moon has a time span of 29.5 days or to be more accurate approx 29 days, 12.734 hours.

6 0

2 years ago