Answer:
F = 156.3 N
Explanation:
Let's start with the top block, apply Newton's second law
F - fr = 0
F = fr
fr = 52.1 N
Now we can work with the bottom block
In this case we have two friction forces, one between the two blocks and the other between the block and the surface. In the exercise, indicate that the two friction coefficients are equal
we apply Newton's second law
Y axis
N - W₁ -W₂ = 0
N = W₁ + W₂
as the two blocks are identical
N = 2W
X axis
F - fr₁ - fr₂ = 0
F = fr₁ + fr₂
indicates that the lower block is moving below block 1, therefore the upper friction force is
fr₁ = 52.1 N
fr₁ = μ N
a
s the normal in the lower block of twice the friction force is
fr₂ = μ 2N
fr₂ = 2 μ N
fr₂ = 2 fr₁
we substitute
F = fr₁ + 2 fr₁
F = 3 fr₁
F = 3 52.1
F = 156.3 N
Answer:
(C) Average Velocity = 25 m/s due North
Answer:
e = Δφ / Δt induced emf is proportional to enclosed flux
Also φ = B * A flux is proportional to area and enclosed field
If the induced emf e increases with time than the flux and hence the magnetic field is increasing with time (replace B with G)
Since e = ΔG * A / Δt if e is linear then G must also be linear and be proportional to the time
Answer : 6.022• 10^23 atoms of potassium
The second one is correct not sure about the first one sorry
