Answer:
17304 J
Explanation:
Complete statement of the question is :
In the winter activity of tubing, riders slide down snow covered slopes while sitting on large inflated rubber tubes. To get to the top of the slope, a rider and his tube, with a total mass of 84 kg , are pulled at a constant speed by a tow rope that maintains a constant tension of 350 N .
Part A
How much thermal energy is created in the slope and the tube during the ascent of a 30-m-high, 120-m-long slope?
Solution :
= tension force in the tow rope = 350 N
= length of the incline surface = 120 m
= work done by tension force = ?
The tension force acts parallel to incline surface, hence work done by tension force is given as

= height gained by the rider = 30 m
= total mass of rider and tube = 84 kg
Potential energy gained is given as

= Thermal energy created
Using conservation of energy

The correct answer should be c.The kinetic energy of the water molecules decreases.
If the temperature drops that means that the molecules are coming together. If the temperature rises then it means that the molecules are spreading. If the kinetic energy falls down that means that they are slower which means that they are cooler.
Answer:
C. 30.6m
Explanation:
To find the height of the tower, we are to use Newtons law of motion to solve this problem. Since the penny is falling from the top of the tower, it is acted by the acceleration due to gravity. The formula to be used is:

Where H is the height of the tower, t is the time taken to hit the ground, u is the initial velocity and g is the acceleration due to gravity.
Given that, t = 2.5 s, g =9.8 m/s², u = 0 m/s (at the top of tower)

Most of the elements are metals
Momentum = mass x velocity, so 500kg x 2m/s = 1000 kg m/s