Answer:
C. 720 N up
Explanation:
Newton's third law states that:
"When an object A exerts a force on an object B, then object B exerts an equal and opposite force on object A"
In this situation, we can imagine the man to be object A and the bench as object B. The force exerted by the man on the bench is:
720 N, down
So according to Newton's third law, the bench must exert an equal and opposite force on the man. Therefore, the force exerted by the bench must be
720 N, up
An iron core is needed in an electromagnet because it serves to increase the magnetic field created. It has a ferromagnetic properties. <span>An </span>electromagnet<span> is essentially just a battery attached to a coil of wire wrapped around a metal</span>core<span>. </span>
The answer is d) protons were created as the results of the charging process
Answer:
334.314 (kJ)
Explanation:
1) the formula for the required energy is: Q=c*m(Bp-t), where c - 4100 J/kg*C; m - 0.9 kg; Bp - 100.6 C; t - 10 C.
2) according to the formula above:
Q=4100*0.9*(100.6-10)=41*9*906=334314 (J).
