A 6000 kg lorry is reversing into a parking space at a speed of 0.5 m/s but collides with a car. The crumple zone of the car stops the lorry in 1.5 seconds. What was the impact force?

-200 N

Explanation:

Force: This can be defined as the product of mass and acceleration The S.I unit is N

The expression for force is given as

F = m(v-u)/t Equation 1

Where F = Impact force, m = mass of the lorry , v = Final velocity of the lorry , u = initial velocity of the lorry, t = time

Given: m = 6000 kg, v = 0 m/s (the lorry was stopped), u = 0.5 m/s, t = 1.5 s

Substitute into equation 1

F = 6000(0-0.5)/1.5

F = -300/1.5

F = -200 N.

Note: The negative sign shows that the impact force act in opposite direction to the initial motion of the lorry

the assestment will probley apele with cause and effect

answer: at 24 february, 2014 the population gets twice of its initial population.

explanation:

since we have given that

the population for alpha city, t years after january 1, 2004 is given as

first we find out the initial population, i.e. t=0,

so, our quadratic equation becomes,

according to question, we have said that if the population has twice its initial population, then it becomes

so, time taken to reach this above mentioned population is given by

now, we know that time can't be negative so, we take t=9.149 years.

hence, at 24 february, 2014 the population gets twice of its initial population.