Answer: Friction between the two surfaces converts kinetic energy into thermal energy.
Explanation: Friction occurs because no surface is perfectly smooth. Rougher surfaces have more friction between them. Friction produces heat because it causes the molecules on rubbing surfaces to move faster and have more energy.
Answer:
a) The flea's speed when it leaves the ground is 
b) The flea move
upward while it is pushing off
Explanation:
Hi
<u>Knwons</u>
Mass
, Work
and Force 
a) Here we are going to use
, so 
a) Here we are going to use
, so
or
approx.
Answer:
<h2>I don't know the answer but I have explanation </h2>
Explanation:
<h3>Science is further treated in a number of articles. For the history of Western and Eastern science, see science, history of. For the conceptualization of science and its interrelationships with culture, see science, philosophy of. For the basic aspects of the scientific approach, see physical science, principles of; and scientific method.Science can be divided into different branches based on the subject of study. The physical sciences study the inorganic world and comprise the fields of astronomy, physics, chemistry, and the Earth sciences. The biological sciences such as biology and medicine study the organic world of life and its processes. Social sciences like anthropology and economics study the social and cultural aspects of human behaviour.Science, any system of knowledge that is concerned with the physical world and its phenomena and that entails unbiased observations and systematic experimentation. In general, a science involves a pursuit of knowledge covering general truths or the operations of fundamental laws.</h3>
Answer:
4992 J
Explanation:
Force, F = 39 N
Distance, s = 128 m
Work done = force x distance
W = 39 x 128
W = 4992 J
Thus, the work done is 4992 J.