Question

1. the friction that results when two objects have surfaces in contact but are not moving (relative to each other) is:

a. static friction
b. sliding friction
c. kinetic friction
d. rolling friction

1. after curing his salamis with saltpeter, a butcher/physicist hangs them out to dry. if each salami has a mass of 12 kg, which scale will have the highest reading?

a. (a)
b. (b)
c. (c)
d. all will read the same

1. when you quickly accelerate in your car, you feel like you are being pushed into the back of your seat. this is really because...

a. the car has inertia and pulls you back
b. you have inertia, and the car is pushing into you
c. the force of the car on you is greater than you on the car
d. the force of you on the car is greater than the cars on you

1. the force of sliding friction depends partly on which of the following:

a. the speed of the objects relative to each other
b. the surface area in contact
c. the type of surface/materials in contact
d. the shape of the objects in contact

1. in the figure to the right, all four boxes have the same mass. which will undergo the greatest acceleration?

a. diagram a
b. diagram b
c. diagram c
d. diagram d
e. all will undergo the same acceleration

1. a net force of 6.8 n accelerates a 31 kg scooter across a level parking lot. what is the magnitude of the scooters acceleration?

a) 0.22 m/sec²
b. 0.69 m/sec²
c. 3.2 m/sec²
d. 4.6 m/sec²
true/false: select a for true, and b for false. mark your scantron.

1. for any two surfaces in contact, the coefficient of kinetic friction is usually greater than that of static friction.
2. any object with mass also has inertia.
3. air resistance depends on the size and velocity of the moving object.
4. the sun pulls harder on the earth than the earth does on the sun.
5. if your tires are already spinning in the snow, spinning them faster will give a greater force of friction.
6. the shape of an object has no effect on its air resistance.
7. rockets work by pushing off the ground behind them.

Explanation:

Step1: Apply Newton's second law

Newton's second law is \(F = ma\), where \(F\) is the net force, \(m\) is the mass, and \(a\) is the acceleration. We can solve for \(a\) as \(a=\frac{F}{m}\). Given \(F = 6.8\ N\) and \(m=31\ kg\).

Step2: Calculate the acceleration

Substitute the values into the formula: \(a=\frac{6.8}{31}\approx0.22\ m/s^{2}\)

Answer:

a. \(0.22\ m/sec^{2}\)