All categories

3 years ago

A) Describe the energy changes that occur in a waterwheel.

1 answer:

7 0

A) Water is moving from a point of bigger height to a point of a lower height, This changes the kinetic and potential energies of water. Some of the kinetic energy of water is transfered to a waterwheel. This causes water wheel to spin. Spining waterwheel has rotational energy. Also waterwheel is rotating around certain point. This causes friction and there is frictional energy.

B)To light LED we need electric energy. To create electric energy we need a generator. Generator consists of a rotor (a magnet) and a stator (copper wire). If we attach a magnet to waterwheel and a wire somewhere close to waterwheel the electric energy would be induced. This energy can be used to light LED.

You might be interested in

Reggie can do 50 pushups in one minute. If the mass that Reggie is lifting which each push-up is at 92 kg, what must also be mea

Sergio039 [100]

The missing measurement is distance.

8 0

3 years ago

Which is NOT a waste that is removed from the body by the excretory system?

oksian1 [2.3K]

Answer:

C. Blood

Explanation:

All the other ones are removed from the body normally.

8 0

3 years ago

Read 2 more answers

A 2.0-kg ball rolls to the right at 3.0 m/s. A 4.0-kg ball rolls to the left at 2.0 m/s . What is the momentum of the system aft

charle [14.2K]

Answer:

Final momentum after a head on collision is -2kgm/s

Explanation:

One ball moves to the right and the other moves opposite and momentum is a vector quantity so that considering the direction

Initial momenta are P₁=2x3=6kgm/s P₂=4x(-2)=-8kgm/s

Final momentum is the vector sum of P(final)= 6-8= -2 kgm/s

4 0

2 years ago

Starting from rest, a disk rotates about its central axis with constant angular acceleration. In 1.00 s, it rotates 21.0 rad. Du

ELEN [110]

With constant angular acceleration $\alpha$ , the disk achieves an angular velocity $\omega$ at time $t$ according to

$\omega=\alpha t$

and angular displacement $\theta$ according to

$\theta=\dfrac12\alpha t^2$

a. So after 1.00 s, having rotated 21.0 rad, it must have undergone an acceleration of

$21.0\,\mathrm{rad}=\dfrac12\alpha(1.00\,\mathrm s)^2\implies\alpha=42.0\dfrac{\rm rad}{\mathrm s^2}$

b. Under constant acceleration, the average angular velocity is equivalent to

$\omega_{\rm avg}=\dfrac{\omega_f+\omega_i}2$

where $\omega_f$ and $\omega_i$ are the final and initial angular velocities, respectively. Then

$\omega_{\rm avg}=\dfrac{\left(42.0\frac{\rm rad}{\mathrm s^2}\right)(1.00\,\mathrm s)}2=42.0\dfrac{\rm rad}{\rm s}$

c. After 1.00 s, the disk has instantaneous angular velocity

$\omega=\left(42.0\dfrac{\rm rad}{\mathrm s^2}\right)(1.00\,\mathrm s)=42.0\dfrac{\rm rad}{\rm s}$

d. During the next 1.00 s, the disk will start moving with the angular velocity $\omega_0$ equal to the one found in part (c). Ignoring the 21.0 rad it had rotated in the first 1.00 s interval, the disk will rotate by angle $\theta$ according to

$\theta=\omega_0t+\dfrac12\alpha t^2$

which would be equal to

$\theta=\left(42.0\dfrac{\rm rad}{\rm s}\right)(1.00\,\mathrm s)+\dfrac12\left(42.0\dfrac{\rm rad}{\mathrm s^2}\right)(1.00\,\mathrm s)^2=63.0\,\mathrm{rad}$

5 0

3 years ago

A box slides to the right along a horizontal surface which is true about the friction force

mixer [17]

Answer:

It is a force in the direction of the motion that allows the box to move

Explanation:

7 0

2 years ago