The kinetic energy of a book on a shelf is equal to the work done to lift the book to the shelf is false. The kinetic energy on the shelf is zero because it is not in action.
Answer:
f=-1380N
Explanation:
A karate master wants to break a board by hitting the board swiftly with his hand. The master's hand has a mass of 0.30 kg, and as it strikes the board, his hand has a velocity of 23.3 m/s. The master contacts the board for 0.0050 seconds
.the concluding part to the question should be
What is the impact force (impulse) on the board?
solution
from the Newton's second law of motion which states that
the rate of change in momentum is directly proportional to the force applied
f=m(v-u)/t
f=0.3(0-23.3)/0.005
f=-1380N
f=force impact
m=mass of the karates master's hand
t=time for the impact
v=0m/s final velocity
u=initial velocity
Answer:
2513.6 W
Explanation:
Acoustic power = sound intensity × area of hemisphere
Sound intensity = 1 W/m^2
Area of hemisphere = 2πr^2 = 2×3.142×20^2 = 2513.6 m^2
Acoustic power = 1 W/m^2 × 2513.6 m^2 = 2513.6 W
Answer:
Short answer, because copper wire does not have high resistance.
Explanation:
