Answer:
The applied force is greater than the frictional force.
Explanation:
the chair moves at <u>a constant speed</u><u> </u><u>therefore</u><u>,</u><u> </u><u>the</u><u> </u><u>answer</u><u> </u><u>is</u><u> </u><u>not</u><u> </u><u>A</u><u> </u><u>or</u><u> </u><u>C</u><u>.</u>
if there is no friction then the chair <u>would accelerate and it would not be at a constant speed</u><u>.</u>
hence, the only possible answer is B.
A pure substance is a substance that is made with only one type of molecule
Answer:
True
Explanation:
Gravity is a very important force. Every object in space exerts a gravitational pull on every other, and so gravity influences the paths taken by everything traveling through space. It is the glue that holds together entire galaxies. It keeps planets in orbit.
Answer:
a) The gravitational acceleration at the surface of the Moon is g moon=1.67 m/s
2
The ratio of weights (for a given mass ) is the ratio of g-values, so
W
moon
=(100N)(1.67/9.8)=17N.
(b) For the force on that object caused by Earth's gravity to equal 17 N, then the free fall acceleration at its location must be
ag
=1.67m/s
2
. Thus , .
ag
= r 2
Gm
E
⇒
a
g
Gm
=1.5×10
7
m
So the object would need to be a distance of r/R
E
=2.4 "radii" from Earth's center.
Answer:
P = 96 J
Explanation:
Given that,
Weight of the book, W = mg = 8 N
It is placed at a height of 12 m
We need to find the potential energy of the book. The potential energy of an object is given by the formula as follows :
E = mgh
mg = Weight
So, the potential energy of the book is 96 J.
