2. A 6.0 kg mass is pulled along a horizontal surface where the coefficient of friction is 0.20. a) What is the friction force acting on the mass?
b) What force is needed to accelerate it at 0.68 m/s^(2)?

Below

Explanation:

a) To find the force of friction acting on the mass we can use this formula :

     friction = coefficientoffriction x normal force

First we need to find the normal force of this object :

     Fn = mg

          = (6.0)(9.8)

          = 58.8 N

Now we can find the force of friction acting on the object :

     friction = (0.20)(58.8N)

                 = 11.76 N

                 = 12 N (we round this to 2 sig figs)

b) To find the force needed to accelerate this object at 0.68 m/s^2 use this :

     F = ma

     0.68 = x - 11.76 / 6

     x = 15.84

     x = 16 N

Hope this helps! Best of luck <3

the independent variable, or the one that is intentionally manipulated is the speed.

note: the given question is incomplete.

complete question is given below.

which is an example of kinetic energy?

a. the energy stored in ethanol  

b. a hockey puck sliding across the ice  

c. a compressed spring  

d. a ball sitting at the top of a ramp

solution: the kinetic energy is the energy posses by the virtue of the motion of the object.

in the given options, a, c and d are the example of potential energy because it is the energy posses by the virtue of the rest of the object. but option b has the kinetic energy as the object is in motion.

hence, a hockey puck sliding across the ice   is the apex example of kinetic energy.

so, the option (b) a hockey puck sliding across the ice   is the correct option.