A 3.0kg and a 5.0kg box rest side-by-side on a smooth, level floor. A horizontal force of 32N is applied to the 5.0kg pushing it against the 3.0kg box, and, as a result, both boxes slide along the floor. How large is the contact force between the two boxes?
An astronaut weighs 99.0N on the moon, where the acceleration of gravity is 1.62ms^2. How much does she weigh on earth?
A 40.0kg crate is being lowered by means of a rope. Its downward acceleration is 2.00ms^2. What is the force exerted by the rope on the crate?
A person is lowering a bucket into a well with a constant speed. The force exerted by the bucket is;
A) equal to the buckets weight
B) greater than the buckets weight
C) less than the buckets weight, but not zero N
D) zero N
A 30.0kg object slides down a slope which is inclined 27.0 degrees to the horizontal. What is the normal force on the object?
You ride on an elevator that is moving downward with constant speed while standing on a bathroom scale. The reading on the scale is;
A) equal to your true weight,mg
B) more than your true weight, mg
C) less than your true weight, mg
D) could be more or less than your true weight, mg, depending on the value of the speed
A horse pulls a cart with force F. As a result of this force the cart accelerates with constant acceleration. What is the magnitude of the force that the cart exerts on the horse?
A) equal to the magnitude of F
B) less than the magnitude of F
C) more than the magnitude of F
D) zero N
You apply the same force to two objects. Object 1 has mass M and object 2 has mass 5M. The acceleration of object 2 is;
A) five times that of 1
B) the same as that of 1
C) one-fifth as that of 1
D) has no relation to 1
An object rests on an inclined surface. If the inclination of the surface is made steeper, what does the normal force on the object?
C) stays the same
D) normal force is zero N
When an object moves at constant speed on a circular path, which of the following is true?
A) a net force pointing along the direction of motion acts on the object
B) a net force pointing away from the center of the circle acts on the object
C) the net force acting on the object is zero N
D) a net force pointing towards the center of the circle acts on the object
A ball rolls over the edge of a table with a horizontal velocity v ms. The height of the table is 1.6m and the horizontal range of the ball from the base of the table is 20m. What is the magnitude and direction of the ball's acceleration right before it touches the ground?
A person throws a ball horizontally from the top of a building that is 22.0m above the ground level. The ball lands 100m down range from the base of the building. What was the initial velocity of the ball.
A rock is thrown from ground level at some angle above the horizontal with a certain velocity. It reaches its highest point and starts falling down. What is the magnitude of the velocity of the rock right before it hits the ground?
A) equal to its initial vertical velocity
B) equal to its initial horizontal velocity
C) equal to the magnitude of its initial velocity
A bullet is fired from ground level with a speed of 150 ms at an angle of 30.0 degrees above the horizontal at a location where g=10.0 ms^2. What is the horizontal component of its velocity when it is at the highest point of its trajectory?
A projectile is shot from the edge of a vertical cliff 60.0m above the ocean. It has a speed of 100 ms and is fired at an angle of 35.0 degrees below the horizontal. How far from the foot of the vertical cliff does the projectile hit the water?
A child throws a ball with an initial speed of 8 ms at an angle of 40.0 degrees above the horizontal. The ball leaves her hand 1.00m above the ground. What is the magnitude of the balls velocity just before it hits the ground?
A projectile is launched with initial velocity v0 at an angle of 30 degrees above the horizontal. If a second projectile is launched with the same initial velocity but at an angle of 60 degrees above the horizontal;
A) the range of the second projectile will be twice that of the first.
B) the range of the second projectile will be one-half that of the first
C) the ranges of the two projectiles will be identical
D) it is impossible to compare the ranges of the two
Acceleration, mass, force, constant speed, velocity and magnitudes are examined.
Physics: velocity, speed, force, temperature, energy, magnitude, acceleration, wave
1) A particle moves according to the equation x=10t2, where x is in meters and t is in seconds. Find the average velocity for the time interval from 2.0 second to 2.1 second.
A) 41 m/s
B) 100 m/s
2) If A = (12i -16j) and B = (-24i + 10j), what is the magnitude of the vector C = (2A - B)?
3) A room measures 3.0 m by 4.5 m by 6.0 m. The heating and air conditioning ducts to and from the room are circular with diameter 0.30 m, and the air in the room is to be exchanged every 12 minutes. What is the necessary flow speed in the duct? (Assume that the density of the air is constant)
A) 0.6 m/s
B) 1.6 m/s
C) 3.2 m/s
D) 4.1 m/s
5) A 50-kg ice skater is moving at 5 m/s when she grabs the loose end of a rope, the opposite end of which is tied to a pole. She then moves in a circle of radius 1 m around the pole. Determine the force exerted by the rope on her arms.
A) 1250 N
B) 250 N
C) 50 N
D) 1100 N
6) Steam at 1000C is added to ice at O0C. The mass of the steam is 10.0 g and the mass of the ice is 50.0 g. What is the final temperature of the mixture?
7) The speed of a 4.0-kg object is given by v = (2t) m/s, where t is in seconds. At what rate is the resultant force on this object doing work at t = 1 second?
A) 48 W
B) 40 W
C) 56 W
D) 16 W
8) A 10-kg object is initially at the top of a rise, at point A. It then moves down to point B. Choose point B to be the zero level for gravitational potential energy. Find the change in potential energy of the object if point B is 10 m lower than point A.
A) - 980
B) - 10
C) - 100
D) - 98
9) A 3-kg particle has a velocity of (3i - 4j) m/s. Find the magnitude of its momentum.
A) 9 kg.m/s
B) -12 kg.m/s
C) 15 kg.m/s
D) 3 kg.m/s
10) At t = 0, a wheel rotating about a fixed axis at a constant angular acceleration has an angular velocity of 2 rad/s. Two seconds later it has turned 5 complete revolutions. What is the angular acceleration of this wheel?
A) 17 rad/s^2
B) 14 rad/s^2
C) 20 rad/s^2
D) 23 rad/s^2
11) A car of mass 1000 kg moves with a speed of 50 m/s on a circular track of radius 100 m. What is the magnitude of its angular momentum (in kg.m^2/s) relative to the center of the racetrack?
A) 5 x 10^2
B) 5 x 10^6
C) 2.5 x 10^6
D) 2.5 x 10^4
14) How many significant figures are in the following number? 0.0064
15) In order to understand the concept of temperature it is useful to understand
A) the zeroth law of thermodynamics
B) the first law of thermodynamics
C) the second law of thermodynamics
D) none of the above
16) An archer shoots an arrow with a velocity of 45 m/s at an angle of 50 degrees with the horizontal. What is the height of the arrow at a point 150 meters downrange?
A) 4.7 m
B) 47.0 m
C) 5.6 m
D) 56.0 m
17) A sinusoidal wave is described by y=(0.30 m)sin(0.20x-40t ). Determine the wave speed.
A) 100 m/s
B) 133 m/s
C) 150 m/s
D) 200 m/s
18) The exhaust temperature of a Carnot heat engine is 350oC. What is the intake temperature if the efficiency is 25.0%?
20) A house has well-insulated walls. It contains a volume of 100 m3 of air at 300 K. Calculate the energy required to increase the temperature of this diatomic gas by 2oC. Assume it is heating at constant pressure and use Cp=7R/2.
A) 118 kJ
B) 236 kJ
C) 354 kJ
D) 472 K
21) If the speed at some point in a fluid changes with time, the fluid flow is not __________.
22) A bowling ball rolls without slipping on a flat surface. The ball has ___________.
A) rotational kinetic energy
B) translational kinetic energy
C) both a and b
D) neither a or b
23) In uniform circular motion, there is a ____________.
A) constant velocity
B) constant angular velocity
C) zero acceleration
D) net tangential acceleration
24) Linear momentum is ____________.
A) always conserved
B) a scalar quantity
C) a vector quantity
D) unrelated to force
25) If the net force on an object is zero, the object must _______________.
A) be at rest
B) be in motion with constant velocity
C) have zero acceleration
D) none of these