Answer:
It is possible to statically charge objects by rubbing it against carpet fibers, but I'm not sure if that was in the article that you read.
Explanation:
Static charge can build up via carpet fibers.
Answer:
Explanation:
mass of displaced oil = 11 x .9
= 9.9 gm
9.9 x 10⁻³ kg
weight of displaced oil = 9.9 x 9.81 x 10⁻³ N
= .097 N .
buoyant force by oil = .097 N
weight of unknown metal = .1 x 9.8
= .98 N .
weight of metal in oil = .98 - .097
= .883 N .
=
Answer it will move slower:
Explanation: cause the force that’s opposite of it
Answer:
Explanation:
Given that,
Mass of the thin hoop
M = 2kg
Radius of the hoop
R = 0.6m
Moment of inertial of a hoop is
I = MR²
I = 2 × 0.6²
I = 0.72 kgm²
Period of a physical pendulum of small amplitude is given by
T = 2π √(I / Mgd)
Where,
T is the period in seconds
I is the moment of inertia in kgm²
I = 0.72 kgm²
M is the mass of the hoop
M = 2kg
g is the acceleration due to gravity
g = 9.8m/s²
d is the distance from rotational axis to center of of gravity
Therefore, d = r = 0.6m
Then, applying the formula
T = 2π √ (I / MgR)
T = 2π √ (0.72 / (2 × 9.8× 0.6)
T = 2π √ ( 0.72 / 11.76)
T = 2π √0.06122
T = 2π × 0.2474
T = 1.5547 seconds
T ≈ 1.55 seconds to 2d•p
Then, the period of oscillation is 1.55seconds
We have the equation of motion 
, where s is the displacement, a is the acceleration, u is the initial velocity and t is the time taken.
Here displacement = 135 m, Initial velocity = 0 m/s, acceleration = 9.81 
Substituting
A box falls out of a stationary helicopter hovering 135 m above the ground will take 5.25 seconds to reach the ground.
