An isolated system , it does not allow any matter or energy to be exchanged
Answer:
Momentum is 100 kg.m/s
Explanation:
given
mass, m = 5 kg
velocity, v = 20 m/s
To find : momentum (P)
We know that momentum is given by equation:
p = mv
= 5 kg x 20 m/s
= 100 kg.m/s
Answer:
About two kilometers away

Explanation:
Given:
The time gap between the light and sound to travel to the house, 
<em>Since the clouds are formed in the troposphere region of the atmosphere which extends from 8 kilometers to 12 kilometers above the earth-surface and the velocity of light is 300000 kilometers per second so it is visible almost instantly, hence we neglect the time taken by the light to travel to the house from the clouds.</em>
<u>∴Distance between the lightning-strike and the house:</u>

we have the speed of sound as: 
So,



Explanation:
The bonds that keep molecules together break apart and form new bonds during chemical reactions, rearranging atoms into different substances. Each bond takes a distinct amount of energy to either break or form; the reaction does not take place without this energy, and the reactants stay as they were.
Answer:
the magnitude of a uniform electric field that will stop these protons in a distance of 2 m is 10143.57 V/m or 1.01 × 10⁴ V/m
Explanation:
Given the data in the question;
Kinetic energy of each proton that makes up the beam = 3.25 × 10⁻¹⁵ J
Mass of proton = 1.673 × 10⁻²⁷ kg
Charge of proton = 1.602 × 10⁻¹⁹ C
distance d = 2 m
we know that
Kinetic Energy = Charge of proton × Potential difference ΔV
so
Potential difference ΔV = Kinetic Energy / Charge of proton
we substitute
Potential difference ΔV = ( 3.25 × 10⁻¹⁵ ) / ( 1.602 × 10⁻¹⁹ )
Potential difference ΔV = 20287.14 V
Now, the magnitude of a uniform electric field that will stop these protons in a distance of 2 m will be;
E = Potential difference ΔV / distance d
we substitute
E = 20287.14 V / 2 m
E = 10143.57 V/m or 1.01 × 10⁴ V/m
Therefore, the magnitude of a uniform electric field that will stop these protons in a distance of 2 m is 10143.57 V/m or 1.01 × 10⁴ V/m