Newton's Second Law

Compared to a 1kg block of solid iron, a 2kg block of solid iron has twice as much ……

• inertia

• mass

• volume

• all

An object weighs 30N on earth. A second object weighs 30N on the moon. Which the greater mass? (Note: due to its size, the moon has less gravity than the earth.)

• object on moon

• object on earth

• same mass

• depends on air resistance

A 10N falling object encounters 4N of air resistance. The net force on the object is

• 4N

• 0N

• 6N

• 10N

Tags

NGSS.MS-PS2-2

Which of the following has zero acceleration? An object

• moving at a constant velocity

• at rest

• at equilibrium

• all of them

A 10kg block with an initial velocity of 10m/s slides 10m across a horizontal surface and comes to rest. It takes the block 2 seconds to stop. The stopping force acting on the block is about

• 5N

• 10N

• 25N

• 50N

A 10kg block is pushed across a horizontal surface with a horizontal force of 20N against a friction force of 10N. The acceleration of the block in meters per second per second is

• 1

• 5

• 2

• 10

Tags

NGSS.MS-PS2-2

A hockey puck is set in motion across a frozen pond. If ice friction and air resistance are neglected, the forced required to keep the puck sliding at constant velocity is

• equal to the weight of the puck

• the weight of the puck divided by the mass of the puck

• the mass of the puck multiplied by 9.8 m/s

• zero newtons

The figure shows a block of mass m1 on a frictionless, horizontal surface. It is pulled by a light string that passes over a frictionless and massless pulley. The other end of the string is connected to a block of mass m2. Find the acceleration of the blocks in terms of m1,m2,and g.

• $a=\frac{m_1}{(m_1+m_2)}g$

• $a=\frac{m_2}{(m_1+m_2)}g$

• $a=\frac{(m_1+m_2)}{m_1}g$

• $a=\frac{(m_1+m_2)}{m_2}g$

In the figure if $m_2>m_1$ . Consider the pulley to be frictionless. If $m_2$  is released, what will its acceleration be? What is the tension in the string?

•  $T=m_1(a+g)$  

•  $T=m_2(a+g)$  

•  $T=m_1(a-g)$  

•  $T=m_2(a-g)$  

Little Johnny stands at the bottom of the driveway and kicks a soccer ball. The ball rolls northward up the driveway and then rolls back to Johnny. Which one of the following velocity-time graphs most accurately portrays the motion of the ball as it rolls up the driveway and back down?

• A

• B

• C

• D