An indicator of average kinetic energy is temperature. Temperature is directly proportional to Kinetic energy of the molecules of an element.
Answer:
a.
b.
Explanation:
We are given that




a.We have to find the angle


b. We have to find the speed 
According to law of conservation of momentum



Newtons law of gravitation is called the universal law of gravitation because it is applicable for all masses at all distances, independent of the medium.
The cost of boiling 500cm3 of water using the 3kW kettle is 1.35 P.
<h3>
Cost of electricity for 3 kW kettle</h3>
The cost is calculated as follows;
1 unit = 9p /kWh
Total energy consumed by 3 kW kettle, E = P x t
where;
- P is power (kW)
- t is time in (hr)
E = 3 kW x (3 mins/60 mins/hr)
E = 0.15 kWh
Energy cost = 9 p/kWh x 0.15 kWh = 1.35 P
Thus, the cost of boiling 500cm3 of water using the 3kW kettle is 1.35 P.
Learn more about energy cost here: brainly.com/question/13795167
#SPJ1
The imbalance of electric charges within or on the surface of a material or between materials is known as static electricity. When you grab a doorknob, electrons jump from your hand to the knob .which conducts electricity, giving you a shock.
<h3>What is static electricity?</h3>
The imbalance of electric charges within or on the surface of a material or between materials is known as static electricity.
The charge will persist until it can be moved away by an electric current or an electrical discharge.
when we walk on the carpet with socks our feet slide electrons off the carpet. it leads to leaving you with a slightly negative static charge.
When you grab a doorknob electrons jump from your hand to the knob which conducts electricity giving you a shock.
Due to the static electricity jump from your hand to the knob .which conducts electricity giving you a shock.
To know more about static electricity refer to the link ;
brainly.com/question/821085