Motion Problem Solutions

Motion Problem Solutions - Braking Car 2) A car...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Braking Car 2) A car (m=1000kg) is traveling with an ini:al velocity of 30 m / s when it hits its brakes. It takes 2s to stop. A)  How far does it travel while braking? v(t) = v0 + a * t; 0 = 30 + a*2 a= ­15 x(t)=x0+v0*t+.5*a*t^2 xf=0+30*2+.5*( ­15)*4 xf=30m B) Draw a force diagram with proper labels and numbers for the braking car. C Froad on C=10000N Froad on C=15000N Fearth on C=10000N 1C) Draw posi:on, velocity, and accelera:on graphs for the car. x 30 25 20 15 10 5 0.5 1.0 1.5 2.0 v 30 25 20 15 10 5 0.5 1.0 1.5 2.0 a 0.5 -5 - 10 - 15 - 20 - 25 - 30 1.0 1.5 2.0 1) You fire a cannon at a 30° angle. The ini:al velocity is 100 m/s. A)  What is the velocity in the x and y direc:ons? vx = 100 * cos 30 = 86.6 m /s vy = 100 * sin 30 = 50 m / s B)  How long will the cannon ball remain in the air? By conserva:on of energy, the velocity in the y ­direc:on will be  ­50 when it hits the ground. The accelera:on is just due to gravity, so using our equa:ons of mo:on: v(t) = v0+at  ­50 = 50 – 10*t t=10 seconds C)  How far will it go? There is no accelera:on in the x direc:on, so, knowing that it is in the air for 10 seconds: x(t) = x0+vx0t+1/2 a t^2 xf = 0 + 86.6 * 10 + 0 xf=866 meters D)  Draw a force diagram for the cannon ball while it is in the air. The only force would just be the downwards force of gravity. You would need the mass of the cannon ball to get a value for it 1E) Draw posi:on, velocity, and accelera:on graphs for each of the x and y components. x 800 y 120 100 600 80 60 40 200 20 400 2 4 6 8 10 2 4 6 8 10 vx 150 vy 40 20 100 2 50 4 6 8 10 - 20 - 40 2 4 6 8 10 ax 1.0 0.5 ay 2 4 6 8 10 -5 - 10 2 4 6 8 10 - 0.5 - 15 - 1.0 - 20 Fighter Jet 1) A fighter jet is making some maneuvers. The x ­posi:on is ploaed as: 3000 2500 2000 1500 1000 500 1 2 3 4 5 6 7 A) Plot the velocity and accelera:on graphs. v 1000 500 a 400 200 1 - 500 2 3 4 5 6 7 1 - 200 - 400 2 3 4 5 6 7 - 1000 - 1500 - 600 - 800 - 1000 Fighter Jet Part 2 •  The Jet has an ini:al velocity of 300 m/s and an ini:al posi:on of 0. It makes some more maneuvers, put this :me the accelera:on is recorded: 200 100 2 - 100 - 200 - 300 4 6 8 10 12 •  B) Plot the velocity and posi:on graphs v 1400 1200 x 15 000 1000 10 000 800 5000 600 2 4 6 8 10 12 2 4 6 8 10 12 ...
View Full Document

Ask a homework question - tutors are online