Answer:
Resistance = 400000 Ohms
Explanation:
Given the following data;
Voltage = 1200 V
Current = 3 mA = 3/1000 = 0.003 A
To find the resistance;
Voltage = current * resistance
Resistance = 1200/0.003
Resistance = 400000 Ohms
The reaction of radiodecay of carbon C-14 is
C-14 --> N-14 + e- + (ve)
where e- is an electron and (ve) is an electron-type antineutrino.
Basically, when the carbon nucleus (atomic number: 6, mass number: 14) decays, a neutron of the nucleus converts into a proton (therefore, the mass number remains the same, 14, but the atomic number increases by 1, therefore it becomes nitrogen) and releases an electron-antineutrino pair.
So, the correct answer is C), N-14.
Answer:
All are correct except the age of earth. The age of Earth is approximately 4.543 Billion Years.
Answer:
A: 1.962
B: 3.924
Explanation:
g = G *M /R^2
g = 9.807*M/R^2 the gravitational constant of ground level on earth is about 9.807
g = 9.807*5lbs/R^2 the average brick is about 5 pounds.
g = 9.807*5*10^2. I'm assuming the height is around ten feet to help you out.
with these numbers plugged in you get an acceleration of 0.4905 a final velocity after 4 seconds 1.962. It's height fallen after 4 seconds is 3.924.
( M = whatever the brick weighs it's not specified in the question)
(R = the distance from the ground or how high the scaffold is)
(hopefully you can just plug your numbers in there hope this helps)
Answer:
Acceleration will be 
Explanation:
We have given initial speed of the car is 70 km/hr
We know that 1 km = 1000 m
And 1 hour = 3600 sec
So 
It is given that car stops in 12 sec
So final speed of the car v = 0 m/sec
Time t = 12 sec
From first equation of motion v = u+at
So 
( negative sign indicates that speed of the car will constantly decrease )
