Complete Question
The complete question is shown on the first and second uploaded image
Answer:
The minimum mass of 
correct option is E
Explanation:
Free body diagram of the set up in the question is shown on the third uploaded image
The mass of board is 
The length of the board is 
The length extending over the edge is 
The second mass is 
Now to obtain 
we take moment about the edge of the platform
Substituting value
Answer:
2048.63 N
Explanation:
Force: The product of mass and the acceleration of a body. The S.I unit of Force is Newton(N).
From the question
P = F×V.................... Equation 1
Where P = power generated by the car, F = Total resistive force acting on the car, V = Velocity of the car.
make F the subject of the equation
F = P/V................ Equation 2
Given: P = 75.0 hp = (75×745.7) = 55927.5 W, V = 27.3 m/s
Substitute into equation 2
F = 55927.5/27.3
F = 2048.63 N
Hence the total resistive force acting on the car = 2048.63 N
Answer: 0.306
Explanation:
from the question we are given the following
mass of sled (m) = 50 kg
force (f) = 1.75 x 10^2 N = 175 N
distance (s) = 6 m
net work done on the sled = 1.50 x 10 ^2 N = 150 N
acceleration due to gravity (g) = 9.8 m/s^2
coefficient of friction = μ
lets first calculate the frictional force (ff)
ff = μ x m x g = μ x 50 x 9.8 = 490 μ
work done on the slide by the applied force (W1)= f x s = 175 x 6 = 1050 j
work done on the slide by frictional force (W2) = ff x s = 490 μ x 6 = 2940μ j
now the net work done is the work done by the frictional force subtracted from the work done by the applied force
net work done = W1 - W2
150 = 1050 - 2940μ
2940μ = 1050 - 150
μ = 900 / 2940
μ = 0.306
A telescope in space can focus on any object while a telescope on the ground cannot focus on the object it is on
