Answer:
The final speed of the train car is 8.57 m/s.
Explanation:
Given that,
Mass of train car = 1000 kg
Mass of sand = 400 kg
Speed of train car = 12 m/s
We need to calculate the final speed of the train car after the sand is dumped
Using conservation of momentum
...(I)
Put the value in the equation (I)



Hence, The final speed of the train car is 8.57 m/s.
I think the answer is d i think
Answer:
Explanation:
Voltage, V = 12 V
Charge, q = 2 micro coulomb = 2 x 10^-6 C
Work = energy
W = 0.5 x q x V
W = 0.5 x 2 x 10^-6 x 12
W = 12 x 10^-6 J
The answer is B- a positive charge
Answer:

Explanation:
First, we will calculate the inductance of the solenoid by using the following formula:

where,
L = self-inductance of solenoid = ?
μ₀ = permeability of free space = 4π x 10⁻⁷ N/A²
A = Cross-sectional area = 30 cm² = 3 x 10⁻³ m²
N = No. of turns = 2000
l = length = 65 cm = 0.65 m
Therefore,

Now, we will use Faraday's law to calculate the rate of change of current:
