Physics Unit 1 Quiz Review
A particle moves in a circular path of radius r with speed v. It then increases its speed to 5v while traveling along the same circular path. By what factor has the period of the particle changed?
0.2
Rank the launch angles for the five paths in the figure with respect to time of flight, from the shortest time of flight to the longest.
15° < 30° < 45° < 60° < 75°
The magnitudes of two vectors A and B are A = 12 units and B = 7 units. Which of the following pairs of numbers represents the largest and smallest possible values, respectively, for the magnitude of the resultant vector R = A + B?
19 units, 5 units
How many significant figures are in the following numbers? 0.0075
2
The drawing shows three displacement vectors, A, B, and C, which are added in a tail-to-head fashion. The resultant vector is labeled R. Which drawing below shows the correct resultant vector for: A + B − C?
2
A particle moves in a circular path of radius r with speed v. It then increases its speed to 5v while traveling along the same circular path. By what factor has the centripetal acceleration of the particle changed?
25
How many significant figures are in the following numbers? 4.80×10⁻¹³
3
At a certain point along the path in projectile motion, the projectile has a velocity whose scalar components are vx = +30 m/sand vy = +40 m/s. As the projectile moves along the path, what would be its minimum speed?
30 m/s
During a relay race, runner A runs a certain distance due north and then hands off the baton to runner B, who runs for the same distance in a direction south of east. The two displacement vectors A and B can be added together to give a resultant vector R. Which drawing correctly shows the resultant vector?
4
How many significant figures are in the following numbers? 3.000 ✕ 10¹⁵
4
How many significant figures are in the following numbers? 310.0 ± 0.3
4
If vector B is added to vector A, which two of the following choices must be true in order for the resultant vector to be equal to zero?
A and B have the same magnitude and are in opposite directions
A car is traveling on the road shown at a constant speed. Through which segment will the car's acceleration be largest?
B to C
The graph shows the displacement of a particle as a function in time. At which point(s) is the velocity of the particle zero? Check all that apply.
B, E, D
Two balls are thrown from the top of a building, as in the drawing. Ball 1 is thrown straight down at viy = - 20.0 m/s, and ball 2 is thrown with the same magnitude initial y-component of velocity, viy = + 20.0 m/s, but upward at an angle θ with respect to the horizontal. Neglect air resistance. After the balls are released, which ball lands first?
Ball 1
Two balls are thrown from the top of a building, as in the drawing. Ball 1 is thrown straight down at viy = - 20.0 m/s, and ball 2 is thrown with the same magnitude initial y-component of velocity, viy = + 20.0 m/s, but upward at an angle θ with respect to the horizontal. After the balls are released, which ball lands with the greater magnitude of final velocity vf? {Neglect air resistance}
Ball 2
Two balls are thrown from the top of a building, as in the drawing. Ball 1 is thrown straight down at viy = - 20.0 m/s, and ball 2 is thrown with the same magnitude initial y-component of velocity, viy = + 20.0 m/s, but upward at an angle θ with respect to the horizontal. After the balls are released, which ball has the greater acceleration while moving through the air? {Neglect air resistance}
Both balls have the same.
Ball 1 is thrown into the air and it follows the trajectory for projectile motion shown in the drawing. At the instant it is at the top of its trajectory, Ball 2 is dropped from rest at the same height. Which ball reaches the ground first?
Both balls reach the ground at the same time
What is the difference between distance and displacement?
Displacement is a vector, while distance is not a vector.
Two cars are moving in the same positive direction on a straight horizontal road. The acceleration of each car also points in the positive direction. Car 1 has the greater acceleration than Car 2. Which one of the following statements is TRUE in this situation?
In the same time interval, the velocity of Car 1 changes by a greater amount than the velocity of Car 2.
Dimensional analysis cannot give you the numerical value of constants of proportionality that may appear in an algebraic expression.
False
In a machine shop, two cams are produced, one of aluminum and one of iron. Both cams have the same mass. Which cam is larger?
Iron cam
The distance between two cities is 100 mi. Is the number of kilometers between the two cities larger, smaller, or equal to 100?
Larger than 100
Which one of the following statements is FALSE?
Near the earth's surface the acceleration due to gravity has a magnitude of 9.8 m/s2, points downward when the motion is downward, and points upward when the motion is upward.
Must two quantities have the same dimensions if you are dividing them?
No
Must two quantities have the same dimensions if you are multiplying them?
No
A rocket is sitting on the launch pad. The engines ignite, and the rocket begins to rise straight upward, picking up speed as it goes. At about 1000 m above the ground the engines shut down, but the rocket continues straight upward, losing speed as it goes. It reaches the top of its flight path and then falls back to earth. Ignoring air resistance, decide which one of the following statements is true.
Only part of the rocket's motion, from just after the engines shut down until just before it lands, is free-fall.
π(r+R)√[h²+(r-R)²]
The area of the curved surface
How is the magnitude R of the resultant vector R related to the magnitudes A and B of the vectors A and B?
The magnitude of R is less than the sum of the magnitudes: R < A + B.
A coin is dropped vertically (from rest) at the same instant that a rock, from the same initial height, is thrown horizontally (only x-component of velocity). Which will have the greater speed (magnitude of velocity) when reaching the ground? Ignore air resistance.
The rock
If the position of an object is plotted vertically on a graph and the time is plotted horizontally, the velocity of the object at an instant in time is given by:
The slope of the tangent to the curve at that time.
A bicyclist cycles around a circular track and covers the same number of meters per second at all times. Which one of the following is true?
The speed of the bicyclist is constant.
2π(r+R)
The total circumference of the flat circular faces
Only one of the following is possible for a moving object. Which one?
The velocity is zero at one instant, and the acceleration is not zero at that instant.
¹/₃ πh(r²+rR+R²)
The volume
Must two quantities have the same dimensions if you are adding them?
Yes
Must two quantities have the same dimensions if you are equating them?
Yes
Must two quantities have the same dimensions if you are subtracting them?
Yes
After a ball is thrown upward and is in the air, what will its speed do?
decrease then increase
The distance between two points.
length
Choose the correct response to make the sentence true. The component of a vector is _____________ larger than the magnitude of the vector.
never
The figure shows a projectile thrown upward moving in its parabolic path. At what point along its path are the velocity and acceleration vectors for the projectile parallel to each other?
nowhere
After a ball is thrown upward and is in the air, what will its acceleration do?
remain the same
The figure shows a projectile thrown upward moving in its parabolic path. At what point along its path are the velocity and acceleration vectors for the projectile perpendicular to each other?
the highest point
The figure represents the parabolic trajectory of a ball going from A to E. It is set moving at point A and reaches point E just before it strikes the ground. Which is correct regarding the ball's speed (magnitude of velocity) at A compared with its speed (magnitude of velocity) at E?
the speeds are the same.
At each moment during its flight, a projectile has a velocity v and an acceleration a. The components of these variables are: vx = x component of the velocity vy = y component of the velocity ax = 0 ay = - 9.8 m/s². Which of these components remain constant throughout the motion? (Assume that air resistance is absent).
vx, ax and ay are constant
The drawing shows projectile motion at three points along the trajectory. The speeds at the points are v₁, v₂, and v₃. Assume there is no air resistance and rank the speeds, largest to smallest. (Note that the symbol ">" means "greater than".)
v₁ > v₃ > v₂
If a car is traveling eastward and slowing down, what is the direction of the acceleration of the car?
westward
In which one of the following situations can the equations of kinematics NOT be used?
when the acceleration changes from moment to moment
Are members in the highway patrol more interested in average or instantaneous speed as you drive?
your instantaneous speed
