Because the elevator moves at a constant speed, it's in equilibrium and the net force acting on it is zero. Then the tension in the cable exactly equals the magnitude of the elevator's weight, which is
(3000 kg) (9.80 m/s²) = 29,400 N
Answer:
Gravitational force is <u>noncontact</u> force
Explanation:
Contact force occurs due to the contact between two different objects. Non-contact force occurs due to either attraction or repulsion between two objects such that there is no contact between these objects. There is no field linked with the contact force. ... Gravitational force is an example of a non-contact force.
Answer:
b. a lens does not focus all colors of light to the same place.
Explanation:
Chromatic aberration is a defect of a lens. In this defect, the lens is unable to focus the different wavelengths of the light on a single focal point. It is also known as chromatic distortion and color fringing. It is caused by the dispersion of light while passing through a lens. As a result, the image might become blurred and different colors are observed around its edges. It can be corrected by the use of a combination of converging and diverging lenses.
Hence, the correct option will be:
<u>b. a lens does not focus all colors of light to the same place.</u>
Answer:
(a). The initial velocity is 28.58m/s
(b). The speed when touching the ground is 33.3m/s.
Explanation:
The equations governing the position of the projectile are
where 
is the initial velocity.
(a).
When the projectile hits the 50m mark, 
; therefore,
solving for 
we get:
Thus, the projectile must hit the 50m mark in 1.75s, and this condition demands from equation (1) that
which gives
(b).
The horizontal velocity remains unchanged just before the projectile touches the ground because gravity acts only along the vertical direction; therefore,
the vertical component of the velocity is
which gives a speed 
of
C. 90 m
30m per second... and it takes 3 seconds
3x30= 90
