Exam 2: Describing Motion: Kinematics in One Dimension

The figure shows a graph of the position x of two cars, C and D, as a function of time t. According to this graph, which statements about these cars must be true? (There could be more than one correct choice.)

An object is moving with constant non-zero velocity in the +x direction. The velocity versus time graph of this object is

A 2.0-g string that is 0.67 m long is under tension. The string vibrates at 700 Hz tone in its third harmonic, and this vibration causes a sound wave. What is the wavelength of the sound? The Speed of sound in air is 344 m/s.

On a cold day, a piece of metal feels much colder to the touch than a piece of wood. This is due to the difference in which one of the following physical properties of these materials?

If the result of your calculation of a quantity has SI units of kg ·

An ac signal is applied across a inductor and a resistor. If the power factor of this circuit is 0.40 , what is the frequency of the ac signal?

A resistor is made out of a wire having a length L. When the ends of the wire are attached across the terminals of an ideal battery having a constant voltage V0 across its terminals, a current I flows Through the wire. If the wire were cut in half, making two wires of length L/2, and both wires were Attached across the terminals of the battery (the right ends of both wires attached to one terminal, And the left ends attached to the other terminal), how much current would the battery put out?

When two or more different capacitors are connected in parallel across a potential source (battery), which of the following statements must be true? (There could be more than one correct choice.)

By how many decibels does the intensity level of a sound increase when you triple the intensity of a source of sound?

If the velocity of an object is zero at one instant, what is true about the acceleration of that object? (There could be more than one correct choice.)

A circular coil of 20 turns and radius 5.0 cm is placed with its plane oriented at 90° to a uniform magnetic field of 0.10 T. The field is now increased at a steady rate, reaching a value of 0.50 T after 4)0 seconds. What emf is induced in the coil?

If the resistance in a constant voltage circuit is doubled, the power dissipated by that circuit will

A series RLC circuit has a resistor, 2.0-mH inductor and a capacitor connected across a 120-V rms ac source at What is the power factor of this circuit?

An pipe of length L that is open at both ends is resonating at its fundamental frequency. Which statement about the sound is correct?

A car increases its forward velocity uniformly from 40 m/s to 80 m/s while traveling a distance of 200 m. What is its acceleration during this time?

A water rocket can reach a speed of 75 m/s in 0.050 seconds from launch. What is its average acceleration?

The speed of sound through the ground is about 6.0 km/s while the speed of sound in air is 343 m/s. A very powerful explosion occurs some distance away and you feel the ground vibrate 60 Seconds before you hear the sound of the explosion. How far away is the explosion?

An inductor stores energy in its magnetic field.

Salt water has greater density than fresh water. A boat floats in both fresh water and in salt water. Where is the buoyant force greater on the boat?

A racing car accelerates uniformly from rest along a straight track. This track has markers spaced at equal distances along it from the start, as shown in the figure. The car reaches a speed of 140 Km/h as it passes marker 2. Where on the track was the car when it was traveling at half this speed, that is at 70 km/h?