Following statements are true
(i) The leather jacket has a lower tendency to attract electrons than sweater.
When the sweater and the leather jacket are in contact with each other, the leather jacket loses electrons and thus becomes positively charged. the electrons are gained by the sweater and it becomes negatively charges.
The opposite charge attract. so the sweater ( negatively charged) will attract protons ( positively charged) . The leather jacket ( positively charged) will attract the electrons ( negatively charged).
Answer : The process of changing a property of a wave to transmit information is called Modulation.
Explanation :
Modulation is the process of changing the property of wave to transmit information. This is done with the help of modulator.
In modulation, the message signal is superimposed on a high frequency signal. A sine wave ( usually high frequency ) is used as a high frequency carrier wave.
Modulation can be done in many ways like :
(1) Frequency modulation
(2) Amplitude modulation
(3) Pulse modulation
Total time in between the dropping of the stone and hearing of the echo = 8.9 s
Time taken by the sound to reach the person = 0.9 s
Time taken by the stone to reach the bottom of the well = 8.9 - 0.9 = 8 seconds
Initial speed (u) = 0 m/s
Acceleration due to gravity (g) = 9.8 m/s^2
Time taken (t) = 8 seconds
Let the depth of the well be h.
Using the second equation of motion:

h = 313.6 m
Hence, the depth of the well is 313.6 m
Answer:
a) r=4.24cm d=1 cm
b) 
Explanation:
The capacitance depends only of the geometry of the capacitor so to design in this case knowing the Voltage and the electric field


The distance must be the separation the r distance can be find also using

But now don't know the charge these plates can hold yet so
a).
d=0.01m



b).


Answer: Neither Sandra nor Marissa will be in her THR zone.
Explanation:
1) Actual pulse of both Sandra and Marissa : 144 bpm
2) Decrease of 20 bpm ⇒ 144 bpm - 20 bpm = 124 bpm
3) Sandra's TRH is in the range 135 - 172 bpm.
Since 124 < 135, she will be below the range.
4) Marissa's TRH range is 143 - 176 bpm.
Since, 124 < 143, she is below the range
In conlusion, neither Sandra nor Marissa will be in her THR zone.