Answer:
Option A: F/4
Explanation:
Centripetal force,
Where v = speed
r = radius
Since Kinetic Energy,
Writing centripetal force in terms of kinetic energy,
If the initial radius of the circle, r₁ =r
The doubled radius, r₂ = 2r
If the initial kinetic energy,
The halved kinetic energy,
Therefore, the new Centripetal force becomes:
Answer:
Explanation:
given,
mass of hoop = 2.75 Kg
horizontal speed = 4.5 m/s
angle with horizontal = 25°
m g l sin θ = m ( v² - u² )
g l sin θ = ( v² - u² )
9.8 x 3 x sin 25° = ( v² - 4.5² )
12.425 = v² - 20.25
v² = 32.675
v = 5.72 m/s
Rotational
Answer:
f = 0.84 m
Explanation:
given,
near point of the distance from eye(d_i) = 0.60 m
distance he can read (d_o)= 0.350 m
focal length of the contact lens = ?
now,
Using lens formula
f = 0.84 m
Hence, The focal length of the contact lens that person needed is equal to
f = 0.84 m
The size (distance) is the same the direction is opposite so one displacement is 180 degrees different to the other.