Answer: 3.9 MW
Explanation:
1 W = 1 J/s
260000 J/s (15 s) = 3,900,000 = 3.9 MW
As we know that friction force on box is given by

here we know that

here we have
m = 12 kg

so now we have

now we will have


so it required minimum 49 N(approx) force to move the block
A). period is time
b). amplitude can be almost anything that waves . . . length, voltage, pressure, current etc.
But not hertz.
c). frequency ... "oftenness ... reciprocal time. the only item on this list that CAN be measured in Hertz.
d). wavelength ... length units
Answer:the acceleration will double
Explanation: