Answer:
, repulsive
Explanation:
The magnitude of the electric force between two charged particles is given by Coulomb's law:
where:
is the Coulomb's constant
are the two charges of the two particles
r is the separation between the two charges
The force is:
- repulsive if the two charges have same sign
- Attractive if the two charges have opposite signs
In this problem, we have two electrons, so:
is the magnitude of the two electrons
is their separation
Substituting into the formula, we find the electric force between them:
And the force is repulsive, since the two electrons have same sign charge.
<span>Nuclei of u-238 atoms are </span><span>unstable and spontaneously emit alpha particles.</span>
Assuming it is on a horizontal surface:
friction = μR
R = 20g (g is gravity 9.81)
so Friction = 0.085 x 20g
Work done is force x distance
so Work done = 0.085 x 20g x 28
= 466.956 J
Answer: 
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.
Q = Heat absorbed=
Joules
m= mass of copper = 454 g
c = specific heat capacity = 
Initial temperature of the copper = 
= 23.0°C
Final temperature of the water = 
= ?
Change in temperature ,
Putting in the values, we get:
The final temperature of copper will be
