Folk song
(Word cap filler)
Let us examine the given situations one at a time.
Case a. A 200-pound barbell is held over your head.
The barbell is in static equilibrium because it is not moving.
Answer: STATIC EQUILIBRIUM
Case b. A girder is being lifted at a constant speed by a crane.
The girder is moving, but not accelerating. It is in dynamic equilibrium.
Answer: DYNAMIC EQUILIBRIUM
Case c: A jet plane has reached its cruising speed at an altitude.
The plane is moving at cruising speed, but not accelerating. It is in dynamic equilibrium.
Answer: DYNAMIC EQUILIBRIUM
Case d: A box in the back of a truck doesn't slide as the truck stops.
The box does not slide because the frictional force between the box and the floor of the truck balances out the inertial force. The box is in static equilibrium.
Answer: STATIC EQUILIBRIUM
-- The area under a velocity/time graph, between two points in time, is the difference in displacement during that period of time.
-- The area under a speed/time graph, between two points in time, is the distance covered during that period of time.
Answer:
Hey
(note you have forgotten your diagram so this may not be what you where hoping for.)
The important discovery that galilao made was that he proved that <em><u>all objects no matter their mass fall at the same rate.</u></em>
That is to say that a bowling ball falls at the same rate as a truck.
The answer is it will supply 1.1 x 10⁹ J of energy each second.
we can calculate this by using the following equation;
P = W/t
<span>W = P x t
</span><span>and by work energy relation;
E = W = P x t
</span>1 watt = 1j/s
1megawatt = 1000000 = 10⁶ j/s
<span>E = 1100 x 106 x 1 </span>
E = 1.1 x 10⁹ J
