Answer:
t = Δa / v
Explanation:
To know which option is not true, we shall fine a relationship between acceleration (a), velocity (v), time (t) and radius (r). This is illustrated below:
Acceleration can simply be defined as the rate of change of velocity with time. Mathematically, it is expressed as shown below:
Acceleration = change in velocity / time
a = Δv / t ..... (1)
But
Δv = v₂ – v₁
Substitute the value of Δv into equation (1)
a = Δv / t
a = v₂ – v₁ / t ....... (2)
From equation (1), make Δv the subject of the equation.
a = Δv / t
Cross multiply
Δv = at .... (3)
From equation (1), make t the subject of the equation.
a = Δv / t
Cross multiply
at = Δv
Divide both side by a
t = Δv /a ...... (4)
From circular motion, centripetal's force is given by:
F = mv²/r
F = ma꜀
Therefore,
ma꜀ = mv²/r
Cancel out m
a꜀ = v²/r
SUMMARY:
a = Δv / t
a = v₂ – v₁ / t
Δv = at
t = Δv /a
a꜀ = v²/r
Considering the options given in question above, t = Δa / v is not a true statement.
Answer:
5 watts
power = work done ÷ time taken
10 j ÷ 2 = 5w
The rotational speed of the two children is the same.
In fact, it is defined as
where
is the angle covered in the time
. As it can be seen, this quantity does not depend on the distance from the centre, so the rotational speed is 4.0 revolutions per minute for both children.
Answer:
D. radiation dose
Explanation:
The amount of energy transferred to electrons by ionizing radiation is the basis of the concept of <u>Radiation dose</u>. Radiation dose, also known as absorbed radiation dose, is the amount of energy deposited in a given mass of a medium by ionizing radiation. The international system of units (SI system) for Radiation absorbed dose and effective dose in radiation measurement are "gray" (Gy) and "sievert" (Sv), respectively.
Answer: Acceleration is 0.25m/s^2
Explanation: