Answer: The control group is the part where you see what happens when you change a variable you want to study/examine. Basically, you need the control group because you need something to see what happens when you change something.
Hope this Helps! :))))
Velocity, unlike speed, includes a direction.
Velocity is a vector quantity which is defined by magnitude and direction.
Speed is a scalar quantity. It is the rate at which an object moves regardless of which direction.
Answer:
The magnitude of F when t=4 s=146.64 N
Explanation:
We are given that
Mass of crate,m=6.00 kg
Height of crate above its initial position is given by
We have to find the magnitude of F when t=4.00 s
Differentiate w.r.t t
![\frac{dy}{dt]=2.8+3(0.61)t^2](https://tex.z-dn.net/?f=%5Cfrac%7Bdy%7D%7Bdt%5D%3D2.8%2B3%280.61%29t%5E2)
Now, magnitude of force
Hence, the magnitude of F when t=4 s=146.64 N
m = mass of pellet = 2.10 x 10⁻² kg
x = compression of spring at the time launch = 9.10 x 10⁻² m
h = height gained by the pellet above the initial position = 6.10 m
k = spring constant
using conservation of energy
spring potential energy = gravitational potential energy of pellet
(0.5) k x² = m g h
inserting the values
(0.5) k (9.10 x 10⁻²)² = (2.10 x 10⁻²) (9.8) (6.10)
k = 303.2 N/m
