please answer all questions thank you

Question 1 4 pts What is the wavelength ofa 15 Hz sound wave if the speed of sound in air is 343 mrs? 32m 4?m 23m 1.1m Question 2 4 pts The magnitude of the electrostatic force between a 40 pt: point charge and a 108 11!: point charge is 4 N. How far apart are the charges? 312 I11 0.53 m 1.34 rn 2.11 m 3 Question 3 D 4 ptiT| An emergency siren radiates sound uniformly in all directions. At a distance of 1? m from the siren, the intensity level is 49 db. How many.r watts of power does this siren put out? The threshold of human hearing is 1.0 l 10'12 mez. 0.9 mW 2.4 rnW 0.3 M\"! 1.2 mW Question 4 4 pts Two resistors a 5 D and a 9 {'1 are connected in parallel. A 4 {'1 resistor Is then connected in series with this parallel combination. if a an ideal 6 V battery is then connected across the series-parallel combination. What is the current through the 4 {J resistor? 1.1 JR 0.83 A 0.24 A 1.5 A Question 5 4 pts You double your distance from a sound source that is radiating equally in all directions. What happens to the intensity of the sound? O It is four times the original intensity O It is one-half the original intensity It is two times the original intensity O It is one-fourth the original intensity Question 6 4 pts The magnitude of the potential difference between two parallel plates is 4V. If the plates are separated by 6 cm, what is the magnitude of the electric field between the plates? O 81.4 V/m O 32.8 V/m O 12.9 V/m O 66.7 V/m Question 7 4 pts The resistance of a length of 100 cm wire of cross sectional area 2 x 10-6 m is 400 Q. What is the resistivity of the material from which this wire is made? 8 x 10-4 0.m O 3 x 10 4 0.m 1 x 10-6 0.m O 7 x 10-5 0.m O 3 x 10-4 Q.m Question 8 4 pts A car approaches you at a constant speed, sounding its horn, and you hear a frequency of 76 Hz. After the car goes by, you hear a frequency of 65 Hz. What is the frequency of the sound emitted by the horn? O 105 Hz O 70 Hz O 45 Hz 35 HzQuestion 9 4 pts A factory whistle has a frequency of 1000 Hz. If a listener moves with a speed of 30 m/s away from the whistle, what frequency does this person hear? O 818 Hz O 1072 Hz O 1207 Hz O 912 Hz Question 10 4 pts One of the harmonics of a column of air in a tube that is open at one end and closed at the other has a frequency of 448 Hz, and the next higher harmonic has a frequency of 576 Hz. What is the length of the tube? O 2.18 m O 0.65 m O 0.22 m O 1.34 m Question 11 4 pts A 0.25 kg harmonic oscillator has a total mechanical energy of 4.1 J. If the oscillation amplitude is 0.20 m, what is the frequency? O 4.6 Hz O 17.2 Hz O 10.3 Hz O 38.1 Hz Question 12 4 pts As you are moving very quickly toward a speaker emitting a pure tone, which characteristics of the sound get larger? O Wave length O Amplitude O Frequency O SpeedQuestion 13 4 pts A 3.42 kg mass hanging vertically from an ideal spring on the surface of the earth undergoes simple harmonic motion at a place where g - 9.30 mIsZ. It the spring constant of the oscillator is 12 Nfln, nd the period of oscillation of this setup on a planet where g - 1,60 mrsz. 2.21 s 3.3 5 s 0.95 s 14 s Question 14 4 pts A 901mm wire of rnass 90 g and length 1 tn is under tension. When a transverse wave of frequency 890 Hz travels down the wire. its wavelengm is 0.10 m and it has an amplitude of 15.5 Him. What is the tension in the wire? 9'44 N 1'10 N 239 N 574 N . Question 15 4 pt: Two timr beads are 25 cm apart with no other charges or elds present. Bead A carries 10 of: of charge and bead B carries 1 pic. Which one of the following statements is true about the magnitudes of the electric forces on these beads? The magnitude of the force A exerts on B is equal in magnitude to the force B exerts on A The magnitude of the force A exerts on B is greater in magnitude than the fame B exerts an A The magnitude of the force B exerts an A is greater in magnitude than the force B exerts an A The magnitude of the force B exerts on A is 10 times the magnitude of the force B exerts on A Question 16 4 pt: A +5.0- uC charge is plaoed at each of the three corners of a square of side length 70 mm. One corner of the souare is kept empty. what is the magnitude of the net electrostatic force on a +6.0 uC charge placed at the center of the square? 110 N r: N 1?N 132M Question 17 4 pts Two resistors in series are equivalent to a single 9 Q resistor, and in parallel they are equivalent to a 2 Q resistor. What are the values of these two resistors? O 6 Q and 12 Q O 3 0 and 6 0 O 3 0 and 3 0 O 6 0 and 6 0 Question 18 4 pts Copper wire #1 has a length L and a radius b. Copper wire #2 has a length 2L and a radius 2b. Which statement about the resistance across the ends of the wires is true? O The resistance of wire #1 is equal to that of wire #2. O The resistance of wire #1 is half that of wire #2. The resistance of wire #1 is four times higher than that of wire #2. O The resistance of wire #1 is twice as high as that of wire #2. Question 19 4 pts A 7 Q resistor is connected across the terminals of a 10 V. If 0.5 A current flows, what is the internal resistance of the battery? 0 80 O 20 O 13 0 O 190 Question 20 4 pts If an electron is accelerated from rest through a potential difference of 1500 V, what speed does it reach? O 5.6 x 105 m/s 1.8 x 106 m/s 2.2 x 107 m/s 1.3 x 106 m/s