6. Intro to Forces (Dynamics)

A heavy steel cable attached to a motor is lifting a girder, and the girder is speeding up. Which of the following statements best describes the forces acting on the girder according to Newton's Second Law?

According to Newton's First Law, can there be forces acting on an object that is at rest?

A block of mass $m_1$ is initially at rest on a frictionless horizontal surface. A constant force $F$ is applied to the block for a time interval $t$. What is the final speed $u_f$ of block 1 at the end of the time interval?

According to Newton's Second Law, if the net force acting on an object is doubled while its mass remains constant, what happens to the object's acceleration? $F=ma$

If your physics textbook is sliding to the right across a horizontal table and slowing down, which of the following statements best explains the $\mathrm{net} \mathrm{force}$ acting on the book?

Which statement is true according to Newton's First Law of Motion?

A particle moves along the x-axis so that its position as a function of time is given by $x=2t^3-9t^2+12t$, where $x$ is in meters and $t$ is in seconds. At what time or times is the particle moving to the right at maximum speed?

Which of the following situations involves an unbalanced force acting on an object?

When performing the classic egg drop demonstration, how do $\mathrm{balanced}$ and $\mathrm{unbalanced}$ forces explain why the egg falls into the water after the support is quickly removed?

Two balls of different masses ($m\_1$ and $m\_2$) are dropped from the same height ($h$) in the absence of air resistance. Which ball hits the ground with greater speed ($v$)?

A truss is in static equilibrium with a horizontal member AB subjected to a load. If the member AB is oriented horizontally and supports a vertical load of $1000N$ at its midpoint, what is the force in member AB according to Newton's First and Second Laws?

According to Newton's First and Second Laws, which of the following best explains why a lightbulb in a simple circuit will not light if the circuit is open at one point?

Which of the following examples describes a situation where a car is experiencing a net force ($F\_\mathrm{net}$)?

Which of the following best describes Galileo's contribution to the study of motion?