Answer:
F = f from Newton’s first law.
Explanation:
since the desk is moved in a straight line at a constant speed, newton first law tell us that the two forces must be equal.
Newton's First Law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. since the table has been set in motion by the 400 N force, it will remain in motion unless it is been acted upon by an external force, and this means that the 400 N must be equal to the frictional force for it to have been in motion in the first instance.
Answer:
Find answers below.
Explanation:
1. Radiant: the energy of light.
2. Light: makes it possible to see things.
3. Sun: a source of light. This source of light is referred to as solar energy and it's renewable source of energy.
4. Crest: top of wave. Thus, it's typically the highest part of an electromagnetic wave.
5. Trough: bottom of wave. Thus, it's typically the lowest part of an electromagnetic wave.
6. Wavelength: distance from one point on one wave to the same point on the next wave.
7. Infrared light: it has longer wavelengths than visible light.
8. X-rays: shorter wavelengths than visible light.
Electromagnetic waves is a propagating medium used in all communications device to transmit data (messages) from the device of the sender to the device of the receiver.
An electromagnetic spectrum refers to a range of frequency and wavelength that an electromagnetic wave is distributed or extends. The electromagnetic spectrum comprises of gamma rays, visible light, ultraviolet radiation, x-rays, radio waves, and infrared radiation.
Answer:

Given:
Initial velocity (u) = 30 m/s
Final speed (v) = 0 m/s
Acceleration (a) = - 1.5 m/,s²
To Find:
Time in which train will come to rest (t).
Explanation:

So,
Time in which train will come to rest = 20 seconds
From the law of conservation of momentum
m1u1+ m2u2= m1v1+ m2v2
110*8+ 110*-10= 110*-10 + 110* v2
v2= 8 m/sec