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
Answer:
Angular frequency will increase
No change in the amplitude
Explanation:
At extreme end of the SHM the energy of the SHM is given by

here we know that

now at the extreme end when one of the mass is removed from it
then in that case the angular frequency will change

So angular frequency will increase
but the position of extreme end will not change as it is given here that the top block is removed without disturbing the lower block
so here no change in the amplitude
Answer:
the previous correct answer is b
Explanation:
When the circuit is closed in the system, a current is induced that follows the lenz law, which opposes the change that is occurring and therefore the coil increases and the idicidal current in the ring must reach the maximum oppositing is the current of the coil, so quiet force is repulsion
Consequently, the previous correct answer is b
Answer:
D
Explanation:
Two plane mirrors are inclined at 70∘. A ray incident on one mirror at incidence angle θ after reflection falls on the second mirror and is reflected from there parallel to the first mirror, The value of θ is. ∴(θ)=50∘.