Answer:
6 days.
Explanation:
From radioactivity, The expression for half life is given as,
R/R' = 2⁽ᵃ/ᵇ)................... Equation 1
Where R = original mass of the radioactive substance, R' = Remaining mass of the radioactive substance after decay, a = Total time taken to decay, b = half life.
Given: R = 80 g, R' = 10 g, b = 2 days.
Substitute into equation 1
80/10 = 2⁽ᵃ/²⁾
8 = 2⁽ᵃ/²⁾
2³ = 2⁽ᵃ/²)
Equating the base and solving for a
3 = a/2
a = 2×3
a = 6 days.
Answer:
the acceleration required is 1.37m/s^2
Explanation:
The car is having a constant velocity movement, so if we calculate the time to reach 897m, we can use it to find the acceleration the policeman need to apply to reach the car.

the policeman is traveling with a constant acceleration starting from rest so:

Answer:
second one is correct that is right
2 because that’s correct I I I I I I I I I I I I I I I I I I I
Answer:
when a element of 1 group take part in reaction, its atom looses outer electron and form positively charged ions called Cation.
Explanation: