To make sure I don’t has 35 012345 bishops
E=Eq,
where F is the electrostatic force (or Coulomb force) exerted on a positive test charge q.
To slow down or reduce speed.
Answer:
0.7 mJ
Explanation:
<u>Identify the unknown: </u>
The work required to turn the dial from 180° to 0°
<u>List the Knowns: </u>
Capacitance when the dial is set at 180°: C = 350 pF = 350 x 10^-12 F Capacitance when the dial is set at 0°: C = 100 pF = 100 x 10^-12 F
Voltage of the battery: V = 130 V
<u>Set Up the Problem:</u>
<em><u>Energy stored in a capacitor: </u></em>
U_c=1/2*V^2*C
=1/2*Q^2/C
<em><u>When the dial is set at 180°:</u></em><em> </em>
U_c=1/2*(130)^2*350*10^-12=10^-4
Q=√2*U_c*C=4*10^-7
<u><em>When the dial is set at 0°:</em></u>
U_c=1/2*(4*10^-7)^2/100*10^-12
=8*10^-4 J
<u><em>Solve the Problem: </em></u>
ΔU_c=7*10^-4 J
=0.7 mJ
note:
there maybe error in calculation but method is correct
Answer: 2960N
Explanation:
According to newtons first law of motion, force = mass × acceleration
To get acceleration,
Acceleration = velocity/time
Velocity = 80km/hr
Converting the velocity to m/s
80×1000/1×3600
velocity = 22.2m/s
Time = 9secs
Acceleration=22.2/9
Acceleration = 2.47m/s²
The get the force
F= 1200×2.47
F = 2960N