a macopolo of a mass 1200000g travelling at 72km/h is brought to rest in 4s.with the aid of a diagram,find its (a)average retardation (b)average breaking distance (c)the total distance moved during deceleration
a) Ft = change in mv.
Put mass in kg and v in m/s. Solve for F. F = mv/t
b) x = 1/2(v + 0)t
c) how is this different than b)?
And what is a macopolo?
To find the answers to the given questions, we'll use the equations of motion. Let's break down the problem step by step:
(a) Average retardation:
The formula for average retardation is given by the equation:
retardation = (final velocity - initial velocity) / time
We can convert the mass of the macopolo from grams to kilograms by dividing it by 1000:
mass = 1200000g / 1000 = 1200kg
The initial velocity of the macopolo is 72 km/h, which needs to be converted to m/s:
initial velocity = (72 km/h) * (1000 m/km) / (3600 s/h) = 20 m/s
The final velocity is 0 m/s since the macopolo comes to rest.
Now, we can substitute the values into the equation:
retardation = (0 m/s - 20 m/s) / 4s = -5 m/s²
Therefore, the average retardation is -5 m/s² (negative because it represents deceleration).
(b) Average breaking distance:
The formula for average breaking distance is given by the equation:
breaking distance = (initial velocity^2) / (2 * retardation)
Substituting the values we already know:
breaking distance = (20 m/s)^2 / (2 * -5 m/s²) = 40 m²/s² / -10 m/s² = -4 m
Since the distance cannot be negative, we take the absolute value:
average breaking distance = | -4 m | = 4 m
Therefore, the average breaking distance is 4 meters.
(c) Total distance moved during deceleration:
The formula relating distance, initial velocity, final velocity, and time is given by the equation:
distance = (initial velocity + final velocity) / 2 * time
Substituting the values we already know:
distance = (20 m/s + 0 m/s) / 2 * 4s = 20 m/s / 2 * 4s = 40 m
Therefore, the total distance moved during deceleration is 40 meters.