Against the park ranger's advice, a visitor at a national park throws a stone horizontally off the edge of a 83 m high cliff and
1 answer:
You might be interested in
Answer:
(a) The net force is 80.394 N
The acceleration of the crate is 0.804 m/s²
(b) the final velocity of the crate is 5.02 m/s
Explanation:
Given;
mass of the crate, m = 100 kg
applied force, F = 250 N
angle of inclination, θ = 45°
coefficient of friction, μ = 0.12
Applied force in y-direction,
Applied force in x-direction,
The normal force is calculated as;
N + Fy -W = 0
N = W - Fy
N = (100 x 9.8) - 176.78
N = 980 - 176.78 = 803.22 N
The frictional force is given by;
Fk = μN
Fk = 0.12 x 803.22
Fk = 96.386 N
(a) The net force is given by;
Apply Newton's second law of motion;
F = ma
(b) the velocity of the crate after 5.0 s
Answer:
They have a dual wave-particle nature.
Explanation:
Electromagnetic waves consist of periodic oscillations of electric and magnetic field in a plane perpendicular to the direction of motion of the wave (in fact, they are also classified as transverse waves).
Electromagnetic waves have a wave nature, however they also have particle nature - in fact, it has been proved in some experiment (e.g. photoelectric effect) that in some conditions they act as packets of particles - called photons. Therefore, the option
They have a dual wave-particle nature.
is correct.
Other options are wrong because:
They are all invisible. --> False because visible light (which is part of the electromagnetic spectrum, so they are electromagnetic waves) is visible
They can only travel without a medium. --> False because they can also travel in a vacuum
They are slower than sound waves. --> False because they travel much faster (they travel at the speed of light in a vacuum, , while sound travels at 343 m/s in air, for instance)