Answer:
100 watts x 10 hours = 1,000 watt‐hours = 1 kWh
The electric field E of a charge is defined as E=F/Q where F is the Coulomb force and Q is the test charge.
E=(1/Q)*k*(q*Q)/r², where k=9*10^9 N*m²/C², q is the point charge, Q is the test charge and r is the distance between the charges.
So E=(k*q)/r²
When we input the numbers we get that electric field E of a point chage q is:
E=(9*10^9)*(5.4*10^-8)/0.2²=486/0.04=12150 N/C.
This is roughly E=12000 N/C =1.2*10^4 N/C
The correct answer is B.
Friction makes a moving object slower
At the beginning of a basketball game, a referee tosses the ball straight
up with a speed of 4.6 m/s. a player cannot touch the ball until after it reaches its maximum height and begins to fall down. what is the minimum time that a player must wait before touching the ball? s
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kinemaic equation
v=u-at
0=4.6-9.81xt
t=4.6/9.81 ... about half a second
It is when the air hit the wave and it moves to another direction.
