Newton's 2nd Law Application Questions
Does it require more force to accelerate an empty shopping cart or a full shopping cart? How does this relate to Newton's 2nd Law?
The full shopping cart requires more force.
F=ma
Increasing the mass causes the force to increase
If a 100 N net force acts on a 50 kg car, what will its acceleration be?
F=100 N a=F/m
m=50 kg a=100N/50kg
a=? a=2m/s2
A very small alien (m=2.94kg) travels to four different planets in our solar system: Earth, Mars, Venus and Jupiter. Place the aliens weight on the different planets in order from least to greatest?
Freefall Acceleration Due to Gravity
Mars is 3.72m/s2
Venus 8.872m/s2
Jupiter 24.5 2m/s2
Least to greatest
Mars, Venus, Earth, Jupiter
Calculate the weight of a 90kg Martian on Mars where the freefall acceleration due to gravity is 3.7m/s2? How much would the Martian weigh on earth?
w=? Mars Earth
m=90kg w=mg w=mg
gMars= 3.72m/s2 w=(90kg)(3.7m/s2) w=(90kg)(9.8m/s2)
gEarth=9.8m/s2 w= 333N w=882
What are two variables that can be changed and how could they be changed to increase the acceleration of a cart full of chopped wood being pulled by horses?
Decrease the mass by getting rid of some wood.
Increase the force by adding some more horses
What is the net force on a 2kg skateboard accelerating a rate of 2m/s2?
F=? F=ma
m=2kg F=(2kg)(2m/s2)
a=2m/s2 F=4N
Determine the force of sliding friction when a 3N force is required to drag a 2kg box at 2m/s in a straight line across the counter.
The force of sliding friction is 3N. The box is moving at a constant speed, therefore the net force is 0. The forward applied force must be cancelled out by the force of friction acting in the opposite direction.
After a 50kg car drives off a platform, what is the gravitational force acting on the car (assume the car is on Earth)?
Extra credit: What is the weight of the car when it is on the platform?
f or w=? f= ma or w=mg
m=50kg f = (50kg)(9.8m/s2)
a or g =9.8m/s2 f = 490 N