Answer:
-62.45m/s and +62.45m/s
Explanation:
The formula for relativistic speed
This is the speed of A with respect to B

where
will be the velocity of person 1: 39m/s
will be the velocity of person 2: -31m/s (negative because is travelling in opposite direction)
and
the velocity of light: 100m/s
The velocity of person 1 measured by person 2 is:

The velocity of person 2 measured by person 1 is:


Data:
F (force) = ? (Newton)
k (<span>Constant spring force) = 50 N/m
x (</span>Spring deformation) = 15 cm → 0.15 m
Formula:

Solving:



Data:
E (energy) = ? (joule)
k (Constant spring force) = 50 N/m
x (Spring deformation) = 15 cm → 0.15 m
Formula:

Solving:(Energy associated with this stretching)




Answer:
160N/m
Explanation:
According to Hooke's law which states that the extension of an elastic material is directly proportional to the applied force provided that the elastic limit is not exceeded. Mathematically,
F = ke where
F is the applied force
k is the spring constant
e is the extension
From the formula k = F/e
Since the body accelerates when the block is released, F = ma according to Newton's second law of motion.
The spring constant k = ma/e where
m is the mass of the block = 0.4kg
a is the acceleration = 8.0m/s²
e is the extension of the spring = 2.0cm = 0.02m
K = 0.4×8/0.02
K = 3.2/0.02
K = 160N/m
The spring constant of the spring is therefore 160N/m
False because opposites attract. :)
C I think lol but I have to keep typing