Answer:
Time, t = 8 seconds
Explanation:
An object is thrown upward from the top of a 128-foot building with an initial velocity of 112 feet per second. The height h as a function of time t is given by :
We need to find the time when the object will hit the ground. When it will hit the ground, h = 0
So,
On solving the above quadratic equation, we get the value of t = 8 seconds. So, after 8 seconds the object will hit the ground. Hence, this is the required solution.
The kinetic energy is given by:
We know the mass and the maximum speed, plugging their values in the expression above we have:
Therefore, the answer is d.
Answer:
If I double the current in the inductor, the new total energy will become 4E (option f).
Explanation:
The coil or inductor is a passive component made of an insulated wire that stores energy in the form of a magnetic field due to its form of coiled turns of wire, through a phenomenon called self-induction. In other words, inductors store energy in the form of a magnetic field. The energy stored in the space where there is a magnetic field in the inductor is:
where E is Energy [J], L is Inductance [H] and I is Current [A].
If you double the current in the inductor, then the new value of the current is I'= 2*I. So replacing the new total energy is:
Then:
<em><u>If I double the current in the inductor, the new total energy will become 4E (option f).</u></em>