The correct answer should be B.
The correct answer would be B.
Answer:
ON
Explanation:
Frictional force is a force that opposes the motion of body. It is because of friction that motion can be controlled and even walking is made possible.
Now, on a frictionless surface, there is no opposition to motion. Therefore, to keep the body moving there is no force required.
- If surface lacks friction, motion will continue perpetually without any hinderance.
Answer:
See explaination
Explanation:
The mole balance for a constant-volume batch reactor is given such as, For a first-order isothermal reaction, the time to reach a given conversion is the same for constant-pressure and constant-volume reactors. Also, the time is the same for a reaction of any order if there is no change in the number of moles.
Please kindly check attachment for the step by step solution of the given problem.
Given, half life of a certain radioactive element = 800 years.
Amount of substance remaining at time t = 12.5%
Lets consider the initial amount of the radioactive substance = 100%
Using the half life equation:
A = A₀(1/2)^t/t₁/₂
where A₀ is the amount of radioactive substance at time zero and A is the amount of radioactive substance at time t, and t₁/₂ is the half-life of the radioactive substance.
Plugging the given data into the half life equation we have,
12.5 = 100 . (1/2)^t/800
12.5/100 = (1/2)^t/800
0.125 = (0.5)^t/800
(0.5)^3 = (0.5)^t/800
3 = t/800
t = 2400 years
Thus the object is 2400 years old.
