... The top branch of the 3-branched parallel block ... the 9 and 6 in series ...
is equivalent to a single resistor of 15 ohms.
... The 3-branched parallel block boils down to (30, 10, and 15) in parallel.
That's (1/30 + 1/10 + 1/15)⁻¹ = 5 ohms.
... The 5-ohm-equivalent block and the 20-ohm resistor form a
voltage divider across the battery.
The voltage across the 5-ohm-equivalent block is (5/25 x 30v) = 6v .
... The top branch of the block is equivalent to a (9 + 6) = 15-ohmer.
With 6v across its ends, the current through that branch is (6/15) = 0.4A .
... With 0.4A flowing through it, the 9-ohm resistor is dissipating
I²R = (0.4A)² (9 ohms) = (0.16 A²) (9 ohms) = 1.44 W (choice-3)
This is a classic example of conservation of energy. Assuming that there are no losses due to friction with air we'll proceed by saying that the total energy mus be conserved.

Now having information on the speed at the lowest point we can say that the energy of the system at this point is purely kinetic:

Where m is the mass of the pendulum. Because of conservation of energy, the total energy at maximum height won't change, but at this point the energy will be purely potential energy instead.

This is the part where we exploit the Energy's conservation, I'm really insisting on this fact right here but it's very very important, The totam energy Em was

It hasn't changed! So inserting this into the equation relating the total energy at the highest point we'll have:

Solving for h gives us:

It doesn't depend on mass!
Answer: 2.92 s
Explanation:
Given
Mass of ball is 
The initial velocity of the ball is 
Velocity after the rebound is 
Force during the contact is 
We know, change in momentum is Impulse


Thus, the force is applied for 2.92 s
Answer:
v_average = (d₂-d₁) / Δt
this average velocity is not necessarily the velocity of the extreme points,
Explanation:
To resolve the debate, it must be shown that the two have part of the reason, the space or distance between the two points divided by time is the average speed between the points.
v_average = (d₂-d₁) / Δt
this average velocity is not necessarily the velocity of the extreme points, in the only case that it is so is when there is no acceleration.
Therefore neither of them is right.
Answer:
The answer is "a, c and b"
Explanation:
- Its total block power is equal to the amount of potential energy and kinetic energy.
- Because the original block expansion in all situations will be the same, its potential power in all cases is the same.
- Because the block in the first case has no initial speed, the block has zero film energy.
- For both the second example, it also has the
velocity, but the kinetic energy is higher among the three because its potential and kinetic energy are higher. - While over the last case the kinetic speed is greater and lower than in the first case, the total energy is also higher than the first lower than that of the second.
- The greater the amplitude was its greater the total energy, therefore lower the second, during the first case the higher the amplitude.