Answer:
The power consumed by the air filter is 9.936 watts
Explanation:
It is given that, the secondary coil of a step-up transformer provides the voltage that operates an electrostatic air filter.
Turn ratio of the transformer, 
Voltage of primary coil, 
Current in the secondary coil, 
The power consumed by the air filter is :
...........(1)
For a transformer, 
So, 


So, the power consumed by the air filter is 9.936 watts. Hence, this is the required solution.
Answer:
Explanation:
a. The amplitude is the measure of the height of the wave from the midline to the top of the wave or the midline to the bottom of the wave (called crests). The midline then divides the whole height in half. Thus, the amplitude of this wave is 9.0 cm.
b. Wavelength is measured from the highest point of one wave to the highest point of the next wave (or from the lowest point of one wave to the lowest point of the next wave, since they are the same). The wavelength of this wave then is 20.0 cm. or 
c. The period, or T, of a wave is found in the equation
were f is the frequency of the wave. We were given the frequency, so we plug that in and solve for T:
so
and
T = .0200 seconds to the correct number of sig fig's (50.0 has 3 sig fig's in it)
d. The speed of the wave is found in the equation
and since we already have the frequency and we solved for the wavelength already, filling in:
and
v = 50.0(20.0) so
v = 1.00 × 10³ m/s
And there you go!
Answer:
B.The force of friction between the block and surface will decrease.
Explanation:
The force of friction is given by

where
is the coefficient of friction and
is the normal force.
When the student pulls on the block with force
at an angle
, the normal force on the block becomes

and hence the frictional force becomes
.
Now, as we increase
,
increases which as a result decreases the normal force
, which also means the frictional force decreases; Hence choice B stands true.
<em>P.S: Choice D is tempting but incorrect since the weight </em>
<em> is independent of the external forces on the block. </em>
Answer:
Explanation:
Given
mass of rock 
Elevation of Rock 
Distance traveled by rock with time

where, u=initial velocity
t=time
a=acceleration
here initial velocity is zero
when rock is 5 m from ground then it has traveled a distance of 5 m from top because total height is 10 m



velocity at this time



Answer:
1 percent
Explanation:
It says that only 3 percent of the water is fresh. So it can be 1 percent or 3 percent. But then it says that most of the water is locked up in glaciers and polar ice caps. So the animals would have a hard time getting to this water. So the rest is available for them. Approximately 1 percent is most reasonable.