FORCES AND
NEWTON’S LAWS
Practice Problems
Send the tallest person in your group to grab whiteboard
and marker box
Make sure you have at least 2 people at your table group!
#1
• A Saturn V rocket has a mass of 2.75 x 106 kg and exerts
a force of 3.30 x 107 N on the gases it expels.
• A. What is the net force acting on the rocket upon liftoff?
• B. What is the initial vertical acceleration of the rocket?
#2
• Anna is pushing Olaf on a sled across a flat, snow-
covered patio. The coefficient of static friction between
the sled and the snow is 0.12. The coefficient of kinetic
friction between the sled and the snow is 0.10. Olaf has a
mass of 12.5 kg, and Anna is pushing down on the sled
with a force of 55 N at an angle of 30.0° from the
horizontal.
• Will Olaf and his sled begin to move?
• With what force must Anna push Olaf once he’s moving in order to
keep him moving with a constant velocity?
#3
• Sally, m = 45.0 kg, is sitting on a sled that has a mass of
3.5 kg. The coefficient of static friction between the sled
and the snow is 0.12. If Linus is pulling at an angle of
35.0° to the horizontal, what force would he need to apply
in order to start Sally and her sled moving?
• If Linus keeps pulling with that same force, what is the
acceleration of Sally and her sled? Assume the coefficient
of kinetic friction is 0.08.
#4
• A skier has just begun sliding down a 30.0° incline.
Assume the coefficient of kinetic friction between her skis
and the snow is 0.090. What is her final velocity after
skiing for 4.0 s?
#5
• An Olympic skier coasts down a slope with an angle of
inclination of 37°.(a) Neglecting friction, how many
forces act on the skier?
•
(b) What is the acceleration of the skier?
•
(c) If the skier has a speed of 5 m/s at the top of the
slope, what is his speed when he reaches the bottom
of the 35 m long slope?