Answer:
A)6.15 cm to the left of the lens
Explanation:
We can solve the problem by using the lens equation:
where
q is the distance of the image from the lens
f is the focal length
p is the distance of the object from the lens
In this problem, we have
(the focal length is negative for a diverging lens)
is the distance of the object from the lens
Solvign the equation for q, we find
And the sign (negative) means the image is on the left of the lens, because it is a virtual image, so the correct answer is
A)6.15 cm to the left of the lens
2 is B. 3 is D. 4 is C. I think 5 is A. 6 is A. 7 is D. I think you are all correct. Good Luck!
Answer:1). Distance of far point x=0.9m
Therefore, since the image is virtual
-f=-x = -0.9m
Power of the concave lenses = 1/f = 1/-0.9
= -1.11D
2 ) near point is 21cm = 0.21m
Power = 4-1/near point
= 4/0.21
= 14.2D.
Answer:
The power output of the first motor is, P = 2.0 x 10⁴ watts
Explanation:
Given data,
The height of the building, h = 10 m
The mass of the elevator, m = 1000 kg
The time duration of the motor to do this work, t = 5.0 s
The force acting on the elevator,
F = m x g
= 1000 x 9.8
= 9800 N
The work done by the elevator,
W = F x h
= 9800 x 10
= 98000 J
The power output of the first motor,
P = W / t
= 98000 / 5
= 19600 watts
= 1.96 x 10⁴ watts
Hence, the power output of the first motor is, P = 2.0 x 10⁴ watts
