Answer:
F = 47.6 N
Explanation:
- Newton's 2nd law can be expressed as the rate of change of the total momentum, respect of time, as follows:
- So, in order to find the average force exerted by the skater on the wall, we can find the change in momentum due to the force exerted by the wall (which is equal and opposite to the one exerted by the skater), and divide it by the time interval , as follows:
⇒ Fsk = 47.6 N (normal to the wall)
Answer:
Explanation:
Distance between plates d = 2 x 10⁻³m
Potential diff applied = 5 x 10³ V
Electric field = Potential diff applied / d
= 5 x 10³ / 2 x 10⁻³
= 2.5 x 10⁶ V/m
This is less than breakdown strength for air 3.0×10⁶ V/m
b ) Let the plates be at a separation of d .so
5 x 10³ / d = 3.0×10⁶ ( break down voltage )
d = 5 x 10³ / 3.0×10⁶
= 1.67 x 10⁻³ m
= 1.67 mm.
Answer: Option (c) is the correct answer.
Explanation:
Vapor pressure is defined as the pressure exerted by vapors or gas on the surface of a liquid.
When we increase the temperature of a liquid substance then there will occur an increase kinetic energy of the molecules. As a result, they will move readily from one place to another.
Hence, liquid state of a substance will change into vapor state of the substance. This means that an increase in temperature will lead to an increase in vapor pressure of the substance.
Thus, we can conclude that you can increase the vapor pressure of a liquid by increasing temperature.
I don't like the wording of any of the choices on the list.
SONAR generates a short pulse of sound, like a 'peep' or a 'ping',
focused in one direction. If there's a solid object in that direction,
then some of the sound that hits it gets reflected back, toward the
source. The source listens to hear if any of the sound that it sent
out returns to it. If it hears its own 'ping' come back, it measures
the time it took for the sound to go out and come back. That tells
the SONAR equipment that there IS a solid object in that direction,
and also HOW FAR away it is.
RADAR works exactly the same way, except RADAR uses radio waves.
