Answer: 0.333 h
Explanation:
This problem can be solved using the <u>Radioactive Half Life Formula</u>:
(1)
Where:
is the final amount of the material
is the initial amount of the material
is the time elapsed
is the half life of the material (the quantity we are asked to find)
Knowing this, let's substitute the values and find 
from (1):
(2)
(3)
Applying natural logarithm in both sides:
(4)
(5)
Clearing :
(6)
Finally:
This is the half-life of the Bismuth-218 isotope
Answer:
Explanation:
1. Impulse, I = F.t
The statement impulse is the product of Force and distance is false.
2. F = m g
Force necessary to lift the object depends on the mass of the object.
statement 2 is false.
3. Joule is equal to Newton times meter.
Statement 3 is false.
4. Work done to lift an object is correct statement.
Statement 4 is true.
5. Kinetic energy of an object is due to motion.
Statement 5 is false.
6. Stopping distance is directly proportional to the square of velocity.
If velocity is doubled, stopping distance is quadrupled.
Statement 6 is false.
Answer: 2, the nuclear strong force drops to practically nothing at large distances.
Explanation: The protons and neutrons in the nucleus share subatomic particles called pions. This exchange is what keeps the protons and neutrons stuck together in the nucleus. Despite the strong force being the strongest force, it has a very small range. This is because pions have very short lifespans. So, the strong force would have literally no effect at large distances.
Hope that helped! :)
Answer:
The weight if the block is 10Newtons
Explanation:
The weight of any object is quantity of matter the object contains and it is always acting downwards on such body. This shows that the object is under the influence of gravity.
The weight of an object is calculated as mass of the object × its acceleration due to gravity
W = mg
Give the mass of the brick to be 1kg
g is the acceleration due to gravity = 10m/s²
Weight of the object = 1 × 10
= 10kgm/s² or 10Newtons
