His velocity is 3 m/s in the direction in which he is running in. which.
The relationship between the masses of the Earth, moon and sun and their distances to each other play critical roles in affecting tides
Answer:
20 m
Explanation:
From the equation of motion,
S = ut+1/2gt²................................. Equation 1
Where S = Height, u = initial velocity, t = time, g = acceleration due to gravity.
Note: Because the rocked is being dropped from a height, acceleration due to gravity is positive (g), and initial velocity (u) is negative
Given: t = 2.0 s, g = 10 m/s², u = 0 m/s (dropped from height)
Substituting into equation 1
S = 0(2) + 1/2(10)(2)²
S = 5(4)
S = 20 m
Hence the height of the the cliff above the pool is 20 m
Answer:
Explanation:
No of atoms of Ra in 1 g of sample = 6.023 x 10²³ / 226
N = 2.66 x 10²¹
disintegration constant λ = .693 / half life
half life = 1620 x 365 x 60 x 60 x 24 = 5.1 x 10¹⁰ s
disintegration constant λ = .693 / 5.1 x 10¹⁰
radioactivity dn / dt = λN
= (.693 / 5.1 x 10¹⁰ ) x 2.66 x 10²¹
= .3614 x 10¹¹ per sec
= 3.614 x 10¹⁰ / s
