Answer:
F = 51.3°
Explanation:
The component of weight parallel to the inclined plane must be responsible for the rolling back motion of the car. Hence, the force required to be applied by the child must also be equal to that component of weight:

where,
W = Weight of Wagon = 150 N
θ = Angle of Inclinition = 20°
Therefore,

<u>F = 51.3°</u>
Answer: option (D)
Explanation:
The potential energy of each of the students is given below as
P.E(student A) = mgh, where m = mass of student A, g is acceleration due to gravity and h = height of the high dive structure.
The mass of student B is twice as much as that of A, hence his mass is 2m and his potential energy is given below as
P.E ( student B) =2mgh = 2(mgh)
Recall that the relationship between potential energy and work done is that
Work done = - (change in potential)
For student A, work done = - mgh
For student B, work done = - 2mgh
From the equations above it can be seen that student B will do twice the work in getting to the high dive structure than student A hence validating option D.
Answer:
q = -2 m and q = -0.5 m
Explanation:
For this exercise we must use the equation of the optical constructor
1 / f = 1 / p + 1 / q
where f is the focal length, p and q are the distance to the object and the image, respectively
Let's start with the far vision point, in this case the power of the lens is
P = -0.5D
power is defined as the inverse of the focal length in meter
f = 1 / D
f = -1 / 0.5
f = - 2m
the object for the far vision point is at infinity p = infinity
1 / f = 1 / p + i / q
1 / q = 1 / f - 1 / p
1 / q = -1/2 - 1 / ∞
q = -2 m
The sign indicates that the image is on the same side as the object
Now let's lock the near view point
D = +2.00 D
f = 1 / D
f = 0.5m
the near mink point is p = 25 cm = 0.25 m
1 / f = 1 / p + 1 / q
1 / q = 1 / f - 1 / p
1 / q = 1 / 0.5 - 1 / 0.25
1 / q = -2
q = -0.5 m
the sign indicates that the image is on the same side as the object in front of the lens
Answer:
both technician A and Technician B are correct
Explanation:
Technician A says balance shafts are used to counteract vibration created in the engine. Technician B says proper balancing of the engine is important for smooth operation. Which technician is correct
In piston engine engineering, a balance shaft is an eccentric weighted shaft that counteracts vibrations in engine designs that are not inherently balanced. They were first invented and patented by British engineer Frederick W. Lanchester in 1904. ... .The balance shafts have eccentric weights and rotate in opposite direction to each other, which generates a net vertical force. Unavailability of the balance shaft can cause excessive vibration to the engine thereby damaging the oil pump and resulting to engine failure.
This question is asking: Why does gravity occur? why will your notebook get pulled towards you?