Answer:
v₁ = 2.48m/s, v₂ = 0.02m/s
Explanation:
Momentum p must be conserved. p = mv
1) First person throwing the snow ball. The momentum before the throw:
p = (65kg + 0.045kg) * 2.5 m/s
The momentum after the throw:
p = 65kg * v₁ + 0.045kg * 30m/s
Solving for the velocity v₁ of person 1:
v₁ = ((65kg + 0.045kg) * 2.5 m/s - 0.045kg * 30m/s) / 65kg = 2.48m/s
2) Second person catching the ball. The momentum before the catch:
p = 0.045kg * 30m/s + 60kg * 0m/s
The momentum after the catch:
p = (60kg + 0.045kg) * v₂
Solving for velocity v₂ of person 2:
v₂ = 0.045kg * 30m/s / (60kg + 0.045kg) = 0.02 m/s
Answer:
The magnetic field inside the solenoid would decrease by a factor of 2.
Explanation:
The magnetic field, B, of a solenoid of length L, N windings, and radius b with a current, I, flowing through it is given as:
B = (N * r * I) / L
If the length of the solenoid is doubled, 2L,the magnetic field becomes:
B2 = (N * r * I) / 2L
B2 = ½ B
The magnetic field will decrease by a factor of 2.
It depends on Mass and velocity
I think the answer is 3, population.
Answer:
392 N
Explanation:
Draw a free body diagram of the rod. There are four forces acting on the rod:
At the wall, you have horizontal and vertical reaction forces, Rx and Ry.
At the other end of the rod (point X), you have the weight of the sign pointing down, mg.
Also at point X, you have the tension in the wire, T, pulling at an angle θ from the -x axis.
Sum of the moments at the wall:
∑τ = Iα
(T sin θ) L − (mg) L = 0
T sin θ − mg = 0
T = mg / sin θ
Given m = 20 kg and θ = 30.0°:
T = (20 kg) (9.8 m/s²) / (sin 30.0°)
T = 392 N
