Answer:
D potential energy at the top of the stairs, kinetic energy as she walks down
Explanation:
The potential energy of a body is the energy due to the position of the body.
At the top of the stair case, the student is at a significant height.
Kinetic energy is the energy due to the motion of the body.
As the student descends, the potential energy is changed to kinetic energy.
To find the potential energy;
P.E = mgH
m is the mass
g is the acceleration due to gravity
H is the height of the body
To find the kinetic energy;
K.E = 
m v²
m is the mass
v is the velocity
<span>What's the speed of a sound wave through water at 25° Celsius?
<span> <span><span> <span>A. </span>1,250 m/s</span><span> <span>B. </span>1,500 m/s</span><span> <span>C. </span>750 m/s</span><span> <span>D. </span>1,000 m/s
</span></span></span></span>
<u>Answer:</u>
Option (a)
<u>Explanation :</u>
A stage hand starts sliding a large piece of stage scenery originally at rest by pulling it horizontally with a force of 176 N.
Hence Force applied 
Force on piece of scenery 
µk = 
= 
=
=0.36
coefficient of static friction is 0.36
The pressure in a liquid at a given depth is called the hydrostatic pressure. This can be calculated using the hydrostatic equation:
P = ρgh
P = (1000 kg/m³)(9.8 m/s²)(4 m)
<h2>
P = 39200 Pa</h2>
