Answer:

Explanation:
The acceleration of the train is given by:

where:
u = 5 m/s is the initial velocity of the train
v = 45 m/s is the final velocity of the train
t = 8 s is the time taken for the train to increase the velocity
Substituting numbers into the formula, we find

Answer:
Explanation:
Given
N0 = 20kg (original substance)
decay constant λ = 0.179/sec
time t = 300s
We are to find N(t)
Using the formula;
n(t) = N0e^-λt
Substitute the given values
N(t) = 20e^-(0.179)(300)
N(t) = 20e^(-53.7)
N(t) = 20(4.7885)
N(t) =143.055
To know how much of the original material that is active, we will find N(t)/N0 = 143.055/20 = 7.152
About 7 times the original material is still radioactive
Using lens equation;
1/o + 1/i = 1/f; where o = Object distance, i = image distance (normally negative), f = focal length (normally negative)
Substituting;
1/o + 1/-30 = 1/-43 => 1/o = -1/43 + 1/30 = 0.01 => o = 1/0.01 = 99.23 cm
Therefore, the object should be place 99.23 cm from the lens.
Answer:
Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's activities.
Explanation: