
Actually Welcome to the Concept of the kinematics of a body.
Since, we know that Velocity = Distance / time
hence, V = 20/5 = 4 m/s
hence the velocity of the RC car is 4 m/s westwards direction.
Answer:
Waves; wavelength; electromagnetic energy; ultraviolet light.
Explanation:
Sound are mechanical waves that are highly dependent on matter for their propagation and transmission.
Sound travels faster through solids than it does through either liquids or gases.
Light wave can be defined as an electromagnetic wave that do not require a medium of propagation for it to travel through a vacuum of space where no particles exist.
Hence, sound and light are both found as waves, with a variety of wavelength. The sun, a source of light waves specifically, releases a type of electromagnetic energy. It can be found as UVA or UVB types. These lights give off different levels of ultraviolet light, some of wich can be harmful.
Additionally, the ultraviolet spectrum is divided into three categories and these are; UVA, UVB and UVC.
Explanation:
Given
initial velocity(v_0)=1.72 m/s

using 
Where v=final velocity (Here v=0)
u=initial velocity(1.72 m/s)
a=acceleration 
s=distance traveled

s=0.214 m
(b)time taken to travel 0.214 m
v=u+at


t=0.249 s
(c)Speed of the block at bottom

Here u=0 as it started coming downward

v=1.72 m/s
Answer:
If x₁=12 cm then k=1.7985 N/m
If x₂=15 cm then k=1.4388 N/m
Explanation:
Hanging mass= 22 g=0.022 kg
Acceleration due to gravity g=9.81 m/s²
If x₁=displacement= 12 cm=0.12 m
k= spring constant


∴k = 1.7985 N/m
If x₂=15 cm=0.15 m
Force of the hanging mass is same however the spring constant will change

∴k = 1.4388 N/m
As the mass is not changing the spring constant has to change. That means that here there are two spring one with k=1.7985 N/m and the other with k= 1.4388 N/m