Answer:
Rubbing two objects together may cause large number of electrons to be transferred from one object to the other. True or False.
Answer is True.
Explanation:
When we Rub two different objects, the contact area increases or we can say friction increases. In response of rubbing two materials there is a transfer of electrons from one material to the other material. This causes one subject to become positively charged ( Electron loser) and the other object become negatively charged ( Electron gainer ) This is also called Triboelectric Charging.
Now If contact area of two different rubbing objects will be larger, Friction will be larger , the larger number of electrons would be transferred from one object to other.
The answer for sure is 5 m/s
Answer:
One method to solve this problem is to take the ball and the floor as the system
second method to solve this exercise and we take the system as formed by the ball only
Explanation:
One method to solve this problem is to take the ball and the floor as the system, therefore the forces that occur during the collision are driving force and reaction, internal to the system, therefore the moment is conserved.
A second method to solve this exercise and we take the system as formed by the ball only, in this case there is a change at the moment and this is not preserved, This second case is a little more difficult to solve
Answer:
The airspeed must be 7.78 m/s for the rectangular plate kept at 30°.
Explanation:
By looking at the images below wee see that the airspeed on one side of the rectangular plate decreases the statical pressure over this side. Since over the downside, the pressure still bein the atmospheric pressure. This difference in pressure produces a lift force in the plate. The list force is the net force obtained between the difference of the forces that produce the pressure over the upside and the downside:

Where up and down relate to what movement the forces produce. And p and V are the respective air density and velocity.
When the plate is kept horizontal the lift force balance the moment due to the weight of the plate and considering that both forces act at the same point:

By replacing the known values it is possible to find the plate's weight:


When the plate kept to 30° from the vertical the moment equation balance is written as:

The sine of 30° is due to the weight is 30° oriented, therefore the new value for the airspeed is:






<h2>
Answer:</h2>
5.19 x 10³Hz
<h2>
Explanation:</h2>
The capacitive reactance,
, which is the opposition given to the flow of current through the capacitor is given by;

Where;
f = frequency of the signal through the capacitor
C = capacitance of the capacitor.
Also, from Ohm's law, the voltage(V) across the capacitor is given by the product of current(I) and the capacitive reactance. i.e;
V = I x
[Substitute the value of
=> V = I x
[Make f the subject of the formula]
=> f =
---------------------(i)
From the question;
I = 3.33mA = 0.00333A
C = 8.50nF = 8.50 x 10⁻⁹F
V = 12.0V
Substitute these values into equation (i) as follows;
f =
[Taking
= 3.142]
f = 5.19 x 10³Hz
Therefore, the frequency is closest to f = 5.19 x 10³Hz