Name: _______________________
Free-Fall and Newton’s 2nd Law
Block #: ______
Date: _________
The following picture is a skydiver. Assuming no air-resistance, calculate the following velocities and
distances fallen. Use the equations
vf = vi + gt
and d = ½ gt2
(use acceleration because of gravity on the Earth as 9.8 m/s2). Show all work in the space provided.
t=0s
0 m/s
0m
vf = __________
d = _________
Direction of
down
acceleration: __________
t=1s
vf = __________ d = _________
Direction of
acceleration: __________
t=2s
vf = __________ d = _________
Direction of
acceleration: __________
t=3s
vf = __________ d = _________
Direction of
acceleration: __________
Find the acceleration of the boxes below using Newton’s 2nd law of motion:
1.)
10 kg
Direction: _____________
9N
2N
2.)
a = _____________
2N
a = _____________
10 kg
Direction: _____________
9N
Answer the questions using the picture to the right
Draw and label all four forces acting on the box:
1.) If the pulling force is 150 N and the box doesn’t move, what is the magnitude of friction? _______
2.) If the force of sliding friction is 250 N, what force is necessary to keep the crate sliding at a
constant velocity? _______________
The following is a picture of tandem skydivers where gravity and air-resistance are both forces acting
on them. The first skydiver has a mass of 98 kg and the second skydiver has a mass of 102 kg.
Calculate the net force and acceleration for each picture.
A
Fnet = _________
a = _____________
Direction
of acceleration = __________
Fw = _______
500 N
Fr = _______
Fnet = _________
B
a = _____________
Direction
of acceleration = __________
Fw = _______
1960 N
Fr = _______
Fnet = _________
a = _____________
C
Direction
of acceleration = __________
Fw = _______
2100 N
Fr = _______
Fnet = _________
D
a = _____________
Direction
of acceleration = __________
Fw = _______
1.) At which position (A, B, C, or D) are the skydivers going the slowest? ______________
2.) At which position (A, B, C, or D) are the skydivers going the fastest? ____________
3.) At which position (A, B, C, or D) are the skydivers falling at a constant velocity? ____________