The amount of matter in an object and a fundamental measure of how much it resists changes to its state of motion (inertia).
How 'heavy' something feels when you try to push it, regardless of gravity.
Showing a random 20 of 50 problems.
Example 1
easy
A 4 kg object is pushed with a net force of 24 N. Find its acceleration.
Example 2
easy
A student says "my mass on Mars would be smaller because Mars has less gravity." Is this correct?
Example 3
medium
On the Moon (g=1.6 m/s2) an object weighs 32 N. Find its mass and its weight on Earth (g=9.8 m/s2).
Example 4
easy
Which has more inertia: a 2 kg ball or a 5 kg ball?
Example 5
medium
A scale reads 50 kg for a person. What is their weight in newtons (g=9.8 m/s2)?
Example 6
challenge
A rocket of total mass 1000 kg (including fuel) ejects exhaust at a rate such that the thrust is 15,000 N upward while the rocket lifts off (g=9.8 m/s2). Find the upward acceleration just at liftoff.
Example 7
easy
Is mass a vector or a scalar?
Example 8
medium
A spring scale (calibrated for Earth) reads 24 N when an object hangs from it on the Moon (gmoon=1.6 m/s2). What is the object's mass?
Example 9
hard
Two masses are connected by a string over a frictionless pulley: m1=3 kg on the floor side and m2=5 kg hanging. Find the magnitude of the acceleration (g=10 m/s2).
Example 10
hard
A 5 kg object on a frictionless horizontal surface is pulled by a rope at 30∘ above horizontal with 20 N. Find the horizontal acceleration.
Example 11
medium
An astronaut has a mass of 75 kg. What would their weight be on the Moon where gmoon=1.6 m/s2? Compare this to their weight on Earth (g=9.8 m/s2).
Example 12
easy
An object has a weight of 49 N on Earth where g=9.8 m/s2. What is the mass of the object?
Example 13
easy
A bag of flour weighs 19.6 N on Earth (g=9.8 m/s2). What is its mass?
Example 14
easy
A net force of 12 N gives an object 3 m/s2. Find its mass.
Example 15
medium
Two blocks, 3 kg and 2 kg, are glued together and pushed with 20 N on a frictionless floor. Find the acceleration.
Example 16
medium
A 2 kg block and a 6 kg block are tied together and pulled on a frictionless surface with a 24 N force. Find the acceleration of the system.
Example 17
easy
A toolbox weighs 72 N on a planet where g=12 m/s2. What is its mass?
Example 18
challenge
A balance (lever-style, not a spring scale) on Earth reads 4 kg for an object. What would the same balance read on the Moon?
Example 19
easy
True or false: an object's mass changes when it is moved from Earth to the Moon.