QUESTION: If the
value of g on Earth is
10 N/kg, then what
will be the weight of
a mass of 20 kg;

w = m x g  

= mg

w = 20 x 9.8

20 x 9.8 = 196

The weight of an object with a mass of 20 kg is 196 newtons.

I used the approximate gravitational acceleration but it would be 200N if you used your 10m/s acceleration.

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.