Answer:
Acceleration due to gravity will be 
Explanation:
We have given length of pendulum l = 55 cm = 0.55 m
It is given that pendulum completed 100 swings in 145 sec
So time taken by pendulum for 1 swing 
We have to find the acceleration due to gravity at that point
We know that time period of pendulum;um is given by

So 

Squaring both side


So acceleration due to gravity will be 
In a perfectly ELASTIC collision between two perfectly rigid objects <span>both the momentum and the kinetic energy of the system are conserved.hope it helps</span>
Number 4 I think
the atomic mass is 11 because the mass is the sum of protons and neutrons
Answer:
The moon's gravity pulls the Earth to make tides.
Explanation:
The Moons Gravity Pulls On The Earth With Different Strenght Making High Tide And Low Tide.
Hope This Helps!
Series Circuit
A series circuit there is only one path for the electrons to flow (see image of series circuit). The main disadvantage of a series circuit is that if there is a break in the circuit the entire circuit is open and no current will flow. An example of a series would the the lights on many inexpensive Christmas trees. If one light goes out all of them will.
Parallel Circuit
In a parallel circuit the different parts of the electric circuit are on several different branches. There are several different paths that electrons can flow. If there is a break in one branch of the circuit electrons can still flow in other branches (see image of parallel circuit). Your home is wired in a parallel circuit so if one light bulb goes out the other will stay on.
HOPE THIS HELPS YOU MATE!!
I HAVE ALSO GIVEN THE EXPLANATION THINKING THAT IT MIGHT HELP YOU.
THANK YOU.