All AP Physics 1 Resources
Example Questions
Example Question #41 : Motion In Two Dimensions
An archer has a bow, which can be modeled as a spring. The bow has a spring constant of (that is, for each meter that the string of the bow is pulled back from equilibrium, 700N of force is applied). If the archer pulls back the bow with an arrow of mass and releases it at an angle of above the horizontal, what is the range of the arrow? Neglect air resistance.
Since the problem statement tells us that the bow can be modeled as a spring, we can use the following expression to determined how much energy is stored in the bow:
Where is the spring constant, and is the distance the string of the bow is pulled from equillibrium. Plugging in our values, we get:
Then we can assume that all of this energy is transferred to the arrow as kinetic energy:
Rearranging for initial velocity:
Plugging in our values:
Then we can use the range equation to calculate the range of the arrow. Since we were given no initial or final heights in the problem statement, we will assume that the initial and final heights are the same; thus, the range equation is applicable:
Example Question #42 : Motion In Two Dimensions
An arrow is shot from a height of and at an angle of above the horizontal. If the arrow reaches a maximum height of , what was the arrows initial velocity? Neglect air resistance.
We can use the following kinematic equation to determine the arrow's initial vertical velocity:
Rearranging for initial velocity, and eliminating final velocity:
Substituting in values:
Then using the following equation to determine total initial velocity:
Rearranging for initial velocity:
Plugging in our values:
Example Question #41 : Motion In Two Dimensions
If an arrow is shot with a horizontal velocity of from a height of and travels before hitting the ground, at what angle to the horizontal was the arrow shot at? Neglect air resistance.
We can use the range equation to solve this problem:
Now let's start to rearrange for theta:
Let's stop here and develop an expression for initial velocity in terms that we know"
Rearranging:
Now let's plug this back into the range equation:
Then we can use the following trig identity:
Plugging this into our expression:
Now we can cancel out a cos function to get:
And then:
Rearranging for theta:
We have values for each of these variables, so time to plug and chug:
Example Question #44 : Motion In Two Dimensions
An object with mass slides down an incline plane with slope and height . What does the coefficent of friction have to be in order for the object to not gain velocity?
In order for the object not to gain velocity, all the forces acting on it need to cancel out. The normal force will already cancel with the perpendicular force due to gravity () by definition. In order to find the correct coefficient of friction, we set the magnitude of the force due to friction equal to that of the parallel force due to gravity :
The mass and gravity cancel here.
Example Question #41 : Motion In Two Dimensions
A ball near the surface of the earth has initial velocity . Determine the velocity seconds later.
None of these
Using
Example Question #46 : Motion In Two Dimensions
A car traveling at launches off a ramp of height and length . Determine the maximum height of the car. Ignore air resistance.
None of these
Finding the angle at which the car launches at:
Determining y-component of velocity:
Using conservation of energy in a closed system:
Initially, the car has both kinetic and gravitational potential energy in the y direction, but after, it only has gravitational potential.
Solving for
Plugging in values:
Example Question #47 : Motion In Two Dimensions
A car traveling at launches off a ramp of height and length . Determine the "hang time" of the car. Ignore air resistance.
None of these
Finding the angle at which the car launches at:
Determining component of velocity:
Using conservation of energy in a closed system:
Initially, the car has both kinetic and gravitational potential energy in the y direction, but after, it only has gravitational potential.
Solving for
Plugging in values:
Determine the velocity in the y direction when the car hits the ground
Solving for
Plugging in values:
Now, breaking the jump into two parts, the "up" and the "down" and using
Up:
Down:
Example Question #48 : Motion In Two Dimensions
A car traveling at launches off a ramp of height and length . Determine the horizontal distance traveled while airborne. Ignore air resistance.
None of these
Finding the angle at which the car launches at:
Determining component of velocity:
Using conservation of energy in a closed system:
Initially, the car has both kinetic and gravitational potential energy in the y direction, but after, it only has gravitational potential.
Solving for
Plugging in values:
Determine the velocity in the y direction when the car hits the ground
Solving for
Plugging in values:
Now, breaking the jump into two parts, the "up" and the "down" and using
Up:
Down:
Multiplying by the horizontal velocity:
Example Question #51 : Motion In Two Dimensions
Deep in space Object has mass and is initially traveling with velocity . At , it collides with Object , which has mass and is initially motionless. The two objects stick together.
Assuming the collision took place at the origin, determine the location at , fifty five seconds after the collision.
None of these
Using
Plugging in values:
The momentum will be the same in the final state, so again using
Solving for velocity:
Plugging in values (the total mass is equal to the combined masses:
Using
Plugging in values
Example Question #51 : Motion In Two Dimensions
Deep in space Object has mass and is initially traveling with velocity . At , it collides with Object , which has mass and is initially motionless. The two objects stick together.
Assuming the collision took place at the origin, determine the location of object at , fifteen seconds before the collision.
None of these
Using
Plugging in values
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