In triangle ABC , using Pythagorean theorem
BC = sqrt(AB² + AC²)
r = sqrt(y² + x²) eq-1
taking derivative both side relative to "t"
dr/dt = (1/(2 sqrt(y² + x²) ) ) (2 y (dy/dt) + 2 x (dx/dt))
dr/dt = (1/(2 sqrt(0.5² + 0.5²) ) ) (2 (0.5) (dy/dt) + 2 (0.5) (dx/dt))
dr/dt = (1/(2 sqrt(0.5² + 0.5²) ) ) ( v₁ + v₂)
15= (1/(2 sqrt(0.5² + 0.5²) ) ) ( - 30 + v₂)
v₂ = 51.2 m/s
Answer:
Work done, W = 0 J
Explanation:
It is given that,
Mass of the bag, m = 7 kg
If a person carries a bag of groceries 1.2 m above the ground at constant speed across a 2.7 m room. We need to find the amount of work done on the bag he the process. It is given by :
Where
θ = angle between the force and the direction of motion. Here, θ = 90° (its weight is acting vertically downward and it is moving forward)
Since, cos(90) = 0
⇒ Work done, W = 0 J
So, the work done on the bag is zero. Hence, the correct option is (b) "0 J".
Answer:
Explanation:
Given that,
The half-life of Barium-139 is
A sample contains nuclei.
We need to find the decay constant for this decay. The formula for half life is given by :
Put all the values,
So, the decay constant is .
The final temperature is 83 K.
<u>Explanation</u>:
For an adiabatic process,
Given:-
(the gas is monoatomic)
T = 275 0.30
T = 83 K.