Answer:
t = 4.17 hours
Explanation:
given,
The distance between Sun and Neptune, d = 4.5 billion Km
= 4.5 x 10⁹ Km
= 4.5 x 10¹¹ m
The velocity of light, c = 3 x 10⁸ m/s
The velocity is always equal to displacement by the time.
<em>V = d / t m/s</em>
∴ t = d / V
= 4.5 x 10¹¹ m / 3 x 10⁸ m/s
= 15,000 s
= 4.17 h
Hence, the time taken by the light rays to reach the Neptune is, t = 4.17 h
Answer:
Explanation:
Velocity of plane relative to ground V_pg = ?
Given the velocity in vector form ,
velocity of plane relative to air V_pw = 120 cos30 i + 120sin30j
V_wg = 60 i
V_pg = V_pw +V_wg
= 120 cos30 i + 120sin30j + 60i
= 164 i + 60 j
magnitude
=251 km / h
=
Answer:
D. Drawing a conclusion about something
The work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
<h3>What is normal force?</h3>
The force of contact is called the normal force. When the two surfaces are in contact with each other, then the normal force acts.
This force is applied by the solid bodies on each other in order to prevent the passing through each other.
A box slides down a frictionless incline, gaining speed. For this box, the value of work done by normal force has to be found out. Let's analyze the given condition.
- The body is gaining the speed, which means there is a change in kinetic energy.
- The change in kinetic energy is equal to the work done.
- The friction force is the product of coefficient of the friction and normal force.
- The friction force for the given case is zero. Thus, the normal force must be equal to the zero.
Thus, the work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
Learn more about the normal force here;
brainly.com/question/10941832
