Explanation:
The net force along the horizontal direction is

where f is the frictional force. We can find the frictional force by looking at the vertical forces acting on the couch:

From the definition of frictional force,


Therefore, the net force on the couch is

Answer:
1800 N
Solution:
Impulse = mΔv = m * (u - v) .
here m = 100 kg
u = 4 m/s
v = -5 m/s
impulse = 100 x ( 4 - ( -5 ) ) = 900 Kg m/s .
Average reaction Force ( Favg ) = impulse / Δt
Average reaction Force ( Favg ) = 900kg·m/s / 0.5s
Average reaction Force ( Favg ) = 1800 N
Answer:
because when an object approaches the speed of light, it's mass starts to increase exponentially, and would be infinite at the speed of light. It would therefore require MORE than an infinite amount of energy to accelerate even a single electron to the speed of light
Answer:
(B) Resistor only
Explanation:
Alternating Current: These are currents that changes periodically with time.
An LRC Ac circuit is an AC circuit that contains a Resistor, a capacitor and an inductor, connected in series.
In a purely resistive circuit, current and voltage are in phase.
In a purely capacitive circuit, the current leads the voltage by π/2
In a purely inductive circuit, the current lags the voltage by π/2.
Therefore when a alternating current is set up in LRC circuit, in the resistor, the current and the voltage are in phase.
The right option is (B) Resistor only.
The answer is B.
She can measure the mass of the water, marble and the graduated cylinder with the balance.
The volume of the water can be shown on the marked graduated cylinder, the volume of the marble can be measured by the volume difference of the water before and after the marble is put in.