Answer:
Explanation:
Using the lens formula
1//f = 1/u+1/v
f is the focal length of the lens
u is the object distance
v is the image distance
For convex lens
The focal length of a convex lens is positive and the image distance can either be negative or positive.
Given f = 20cm and u = 10cm
1/v = 1/f - 1/u
1/v = 1/20-1/10
1/v = (1-2)/20
1/V = -1/20
v = -20/1
v = -20 cm
Since the image distance is negative, this shows that the nature of the image formed by the convex lens is a <u>virtual image</u>
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For concave lens
The focal length of a concave lens is negative and the image distance is negative.
Given f = -20cm and u = 10cm
1/v = 1/f - 1/u
1/v = -1/20-1/10
1/v = (-1-2)/20
1/V = -3/20
v = -20/3
v = -6.67 cm
Since the image distance is negative, this shows that the nature of the image formed by the concave lens is a <u>virtual image</u>
<u></u>
Answer:
The ratio of the forces is F2/F1 = 1.86
Explanation:
From Newton's second law applied to circular motion, the total force F acting on a body in circular motion is given by
F = mv²/r
Where
m = mass of the body undergoing circular motion
v = linear velocity = ω×r
ω = angular velocity
r = radius of the circular path through which the force acts
So
F = m(ω×r)²/r = mω²×r
Given 2 angular speeds ω1 = 439re/min = 439×2π/60 rad/s = 46 rad/s and
ω2 = 602rev/min = 602×2π/60 rad/s = 63 rad/s
Required to calculate the ratio F2/F1
The mass m and radius r is the same for both forces, so F is dependent on the angular speed
So F2/F1 = ω2²/ω1² = (ω2/ω1)²
F2/F1 = (63/46)² = 1.86
1. Law 1, since there is no other force acting on your body as you stand there, so you will continue to go forward.
2. Law 3, since the swimmer is using opposite forces to propel herself through the water. She generates a force by pushing the water which helps to push her forward.
3. Law 2, since you are giving the motorcycle more energy as a result of the gas being transformed into the energy that helps to accelerate the motorcycle's speed.
To answer your question it is true