Question

Question 9 (1 point) An airplane starts from rest (vo = 0) and accelerates down a...

Question 9 (1 point)

An airplane starts from rest (vo = 0) and accelerates down a runway at 2 m/s2 for 23 s until it takes off. Determine the distance traveled before takeoff.

Question 9 options:

Question 10 (1 point)

An airplane starts from rest (vo = 0) and accelerates down a runway at 4 m/s2 and covers 245 m before it takes off. Determine the time it takes.

Question 10 options:

Question 11 (1 point)

An airplane starts from 2 m/s and accelerates down a runway at 1 m/s2 and covers 446 m before it takes off. Determine the time it takes.

Note, we still need x = vo t + 1/2 a t2, but the formula will still have t and t2.

This is called a quadratic equation. Probably the best way to solve this is with the quadratic formula (your other choices are factoring, completing the square, graphing or numerical methods)

Steps:

Simplify as much as possible and arrange in descending order - that is, get everything on one side of the equation with a zero on the other side and rearrange the terms so that t2 comes first, t comes second and the constant term is lastthe quad formula has a, b, and c which are the coefficients of the t2 term, the t term and the constant term including the positive or negative signsexample:If 4 = 2 t + 1/2 (8) t2Simplify 1/2 (8) = 4, subtract 4 from both sides and rearrange the terms to get 0 = 4t2 + 2t - 4now a = 4, b = 2, c = -4plug these into the quadratic formula and get the two solutions, one when we use the + and the other when we use the - in the formula, just before the square root. Usually we want the positive solution(-2+√(22-4(4)(-4))).(2*4) = 0.78(-2-√(22-4(4)(-4))).(2*4) = -1.3

Question 11 options:

Question 12 (1 point)

Sometimes you have to do the problem in two steps:

A car moving at 16 m/s comes to a stop in 6 s. Find the distance it covers.

Here we see that vO = 16 m/s, v = 0 m/s (comes to a stop), and t = 6 s, and they want x.

We don't have a formula that relates vO , v , t and x. So:

first use v = vO + at to find athen use x = vO t + 1/2 at2 to find x

Question 12 options:

Question 13 (1 point)

If a car moving 13 m/s comes to a stop in 5 seconds, find the acceleration

Question 13 options:

Question 14 (1 point)

A dolphin jumps straight up out of the water at a velocity of 9 m/s. How high

does his body rise above the water before he comes to a stop due to gravity pulling downward at 9.8 m/s2 ?

Reminder: vo is up and acceleration is down - in Physics opposite directions get represented by opposite signs, say, up is positive and down is negative.

if any doubt plzzzz comment first.plzzzzzzzzzzzzz like????

Earn Coins

Coins can be redeemed for fabulous gifts.