Ahorizontal spring with spring constant 290 n/m is compressed by 10 cm and then used to launch a 300 g box across the floor. the coefficient of kinetic friction between the box and the floor is 0.23.what is the box's launch speed?

3.03568 m/s

Explanation:

= Coefficient of kinetic friction = 0.23

k = Spring constant = 290 N/m

x = Compression distance = 0.1 m

g = Acceleration due to gravity = 9.81 m/s²

m = Mass of box = 0.3 kg

= Normal force =

v = Launch velocity

Potential energy of spring

As the potential and kinetic energies are conserved

The launch speed of the box is 3.03568 m/s

i guess it’s a and b

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle