Answer:
Answered
Explanation:
A) The work done by gravity is zero because displacement and the gravitational force are perpendicular to each other.
W= FS cosθ
θ= 90 ⇒cos90 = 0 ⇒W= 0
B) work done by tension
W= Tcosθ×S= 5cos30×2.30= 10J
C) Work done by friction force
W= f×s=1×2.30= 2.30 J
D) Work done by normal force is Zero because the displacement and the normal force are perpendicular to each other.
E) The net work done= Work done by tension in the rope - frictional work
=10-2.30= 7.7 J
Answer:
a = 9.8 m/s²
Explanation:
Acceleration due to gravity on Earth is constant, which is 9.8 m/s²
The sentences are invalid and unsound.
<h3><u>Explanation</u>:</h3>
The fire is defined as the vigorous oxidation of a substance. Now oxidation can occur in presence of any oxidising agent. Like magnesium in presence of nitrogen in high temperature with a dazzling brownish flame to produce magnesium nitride. So fire can be produced in absence of oxygen.
Oxygen is present everywhere in world. So production of a whole room without oxygen is very tough to produce and costly process. So its very unsound.
Answer:

Explanation:
= Avogadro's number = 
e = Charge of electron = 
k = Coulomb constant = 
Z = Atomic number of water = 18
M = Molar mass of water = 0.018 kg/mol
m = Mass of person
The charge is given by

Total number of protons and electrons in each sphere




Electrical force is given by

The electrostatic force of attraction between them is 
KE = 1/2 mv^2 is the relationship betwee mass and kinetic energy