Newton's 2nd Law for 0 Acceleration
Describe Newton's 2nd law. How do force and mass effect an objects acceleration?
Force applied increases acceleration and an increase in mass decreases acceleration
A force of 55 newtons is exerted at an angle of 65 degrees up and to the right. What are the x and y components of this force?
Fx = 23.24 N
Fy = 49.85 N
Lionel Messi kicks a soccer ball, mass of 2.5 kg, with a force of 400 Newtons. What acceleration will the soccer ball experience as Messi kicks it?
169 m/s2
You go to the gym and attach two 45 kg weights to a bar that has a mass of 15 kg. What is the minimum force you must exert to bench press this weight?
1029 Newtons
A force of 45 Newtons is exerted at a 30 degree angle on a 5 kg box and it slides across a table. Determine the normal force
26.5 Newtons
An elevator is moving up at a constant acceleration of 2.5 m/s2, as illustrated in the diagram below: The passenger has a mass of 85 kg. What is the force that the floor exerts on the passenger?
1045.5 Newtons
A jack-o-lantern is placed on a platform scale which reads 12 Newtons and hung from a spring scale which reads 17 Newtons. What must the mass of the jack-o-lantern be?
2.96 kg
A leprechaun’s 5 kg pot of gold is hung via 2
strings. One string is angled at 15 degrees above the horizontal and exerts a 10 Newtons force. Determine the force of the second string which is angled at 20 degrees.
10.3 Newtons
A car, mass of 2500 kg, approaches a stop sign at 30 m/s and comes to a stop in 15 seconds. Determine the coefficient of friction between the road and the tires
0.204
Spider-Man holds the bottom of an elevator with one hand after it has become detached from its cable system. The elevator itself has a mass of 500 kg and currently holds 4 people with a total mass of 200 kg. Determine the force that he exerts on the elevator if the elevator is at rest
6860 Newtons
Spiderman shoots his web at the green goblin, mass of 60 kg, and pulls him towards him at a constant speed. If Spiderman’s webs exert a force of 90 Newtons at an angle of 35 degrees, a) what force must the ground exert upward on the green goblin and b) what is the magnitude of the opposing horizontal friction force? (Assume the green goblin is dragged on the ground and doesn’t move vertically)
a) 536.4 Newtons
b) 73.7 Newtons
Cristiano Ronaldo kicks a soccer ball, mass of 3 kg, and it leaves his foot with a velocity of 3.1 m/s. The coefficient of kinetic friction is 0.25. a) What is the soccer ball’s acceleration? b) How far will the soccer ball travel from Ronaldo’s foot before it comes to a stop?
a. -2.45 m/s2
b. 1.96 meters
A box, mass of 15 kg, is pushed to the left with a constant force of 25 newtons and moves at a constant speed. What is the value of the coefficient of friction?
0.17
Rudolph pulls Santa’s sleigh, mass of 1500 kg, along the snow by using a rope and pulling horizontally. The rope exerts a force of 1800 Newtons at an angle of 45 degrees up and to the right. a) Determine the normal force on the sleigh b) assuming Rudolph pulls the sleigh at a constant velocity of 5 m/s, determine the coefficient of friction between the sleigh and the snow
a) 13,427 N
b) 0.9
Mr Krouse and Mr Composto (mass of 50 kg) decided to go bungee jumping. If Mr Krouse holds the rope up with a force of 600 Newtons after Mr Composto jumps off the cliff with an initial speed of 17.5 m/s, how long will it take for Mr Composto to come to a complete stop?
7.95 seconds