<span>P = energy/t = 0.0025/1E-8 = 250000 W
I(ave) = P/A = 250000/(pi*0.425E-3^2) = 4.4056732E11 W/m^2
I(peak) = 2I(ave) = 8.8113463E11 W/m^2
Electric field E = sqrt(I(peak)*Z0) = 1.8219499E7 V/m, where
free-space impedance Z0 = sqrt(µ0/e0) = 376.73031 ohms</span>
Answer:
58.4 W
Explanation:
The speed of the lawnmower is constant: this means that its acceleration is zero, so the net force on it is zero.
The equation of the forces along the two directions therefore are:
- Perpendicular to the floor: 
- Parallel to the floor: 
where
F is the push of the gardener
R is the normal reaction
m = 20 kg is the mass
g = 9.8 m/s^2 is the acceleration of gravity
is the coefficient of friction

Solving for R,

Substituting into the other equation,

And the power he must supply therefore is the product of this force and the speed:

Answer:
The skin of the tabla is tightened to produce a sound of high pitch.
Explanation:
hope it's helps you ....
The answer is 9.8, did this last year in AP Science