A student constructed a simple electric circuit where two light bulbs were connected in parallel. The circuit power source was a 6.0-V cell. One of the light bulbs had a resistance of 25 ohms, and the other had a resistance of 50 ohms. What was the combined resistance of the light bulbs in the circuit? a) 75ohms

b) 42ohms

c) 25ohms

d) 17ohms

Physics make-up packetname_cle14. an observer hears a sound with a frequency of 400 hz. if the speed of sound is 340 m/s, what is the wavelength of the sound? a. 0.85 mb. 1.2 mc. 2.75 m13.6 m15. as sound travels from steel into air, its speed decreases. if the frequency of the wavedoesn't change, what happens to its wavelength? a. it increases(b) it decreasesc. it remains the samed. there is not enough information given

Part f - example: finding two forces (part i) two dimensional dynamics often involves solving for two unknown quantities in two separate equations describing the total force. the block in (figure 1) has a mass m=10kg and is being pulled by a force f on a table with coefficient of static friction îľs=0.3. four forces act on it: the applied force f (directed î¸=30â above the horizontal). the force of gravity fg=mg (directly down, where g=9.8m/s2). the normal force n (directly up). the force of static friction fs (directly left, opposing any potential motion). if we want to find the size of the force necessary to just barely overcome static friction (in which case fs=îľsn), we use the condition that the sum of the forces in both directions must be 0. using some basic trigonometry, we can write this condition out for the forces in both the horizontal and vertical directions, respectively, as: fcosî¸â’îľsn=0 fsinî¸+nâ’mg=0 in order to find the magnitude of force f, we have to solve a system of two equations with both f and the normal force n unknown. use the methods we have learned to find an expression for f in terms of m, g, î¸, and îľs (no n).

14. a body is projected with velocity vi from a. at the same time another body is projectedvertically upwards from point b withvelocity v2 lies vertically below the highestpoint. both the bodies collide thenv2÷v1is