g Generally the accepted value of acceleration due to gravity is 9.801 
as per the question the acceleration due to gravity is found to be 9.42
in an experiment performed.
the difference between the ideal and observed value is 0.381.
hence the error is -
=3.88735 percent
the error is not so high,so it can be accepted.
now we have to know why this occurs-the equation of time period of the simple pendulum is give as-![T=2\pi\sqrt[2]{l/g}](https://tex.z-dn.net/?f=T%3D2%5Cpi%5Csqrt%5B2%5D%7Bl%2Fg%7D)

As the experiment is done under air resistance,so it will affect to the time period.hence the time period will be more which in turn decreases the value of g.
if this experiment is done in a environment of zero air resistance,we will get the value of g which must be approximately equal to 9.801 
Answer:
8.61 min
Explanation:
original mass= 12.65
first half life = 12.65/2 = 6.325
second half life = 6.325/2 = 3.1625
Note : 3.1625 is the closest to the value (3.115) given so we work with it
total time for decay =17.22
therefore two decays = 17.22/2= 8.61
Answer:
13800 N
Explanation:
Impulse is the product of average force and time expressed as I=Ft where I is the impulse which results into change in momentum, F is the average force and t is the time of impact. Making F the subject of formula then

Substituting I with 13.8 N.s and time, t witg 0.001 s then the average force is calculated as

Therefore, the average force is equivalent to 13800 N
Technician a says that a defective spark plug wire can cause an engine misfire. Technician b says that a defective spark plug can cause an engine misfire. In this case, both technicians are correct.
Technician A is correct, because, Bad spark plug wires can interfere with the electrical current flowing to the engine, making it difficult for the engine to complete the combustion cycle. An incomplete combustion cycle can cause an engine to misfire, also
Technician B is correct because, Dirty spark plugs can cause misfires as well as burned engine oil can prevent the plugs from creating the sparks needed to ignite the fuel after it goes into the cylinder. Old spark plugs can simply break and fail to produce a spark. A broken spark plug is a simple fix, just replace it.
To learn more about Engine misfire, here
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