Consider a metal bar of initial length L and cross-sectional area A. The Young's modulus of the material of the bar is Y. Find the "spring constant" k of such a bar for low values of tensile strain. 2. Ten identical steel wires have equal lengths Land equal "spring constants" k. The wires are connected end to end, so that the resultant wire has length 10L. What is the "spring constant" of the resulting wire?
a. 0.1k
b. k
c. 10k
d. 100k
3. Ten identical steel wires haveequal lengths Land equal "spring constants" k. The wires are slightly twisted together, so that the resultant wirehas length Land is 10 times as thick as each individual wire. What is the"spring constant" of the resulting wire?
a.0.1k
b. k
c. 10k
d. 100k
4. Consider a steel guitar string ofinitial length L=1.00 m and cross-sectional area A = 0.500 m^2 . The Young's modulus of the steel is Y = 2.0 * 10^11 Pa . How far (DeltaL) would such a string stretch under a tension of 1500N?

Abeam of electrons with of wavelength of 7.5 x 10-6 m is incident on a pair of narrow rectangular slits separated by 0.75 mm. the resulting interference pattern is projected onto a screen 10.0 m from the slits. what is the separation of the interference maxima in the resulting interference pattern?

The frequency of vibrations of a vibrating violin string is given by f = 1 2l t ρ where l is the length of the string, t is its tension, and ρ is its linear density.† (a) find the rate of change of the frequency with respect to the following. (i) the length (when t and ρ are constant) (ii) the tension (when l and ρ are constant) (iii) the linear density (when l and t are constant) (b) the pitch of a note (how high or low the note sounds) is determined by the frequency f. (the higher the frequency, the higher the pitch.) use the signs of the derivatives in part (a) to determine what happens to the pitch of a note for the following. (i) when the effective length of a string is decreased by placing a finger on the string so a shorter portion of the string vibrates df dl 0 and l is ⇒ f is ⇒ (ii) when the tension is increased by turning a tuning peg df dt 0 and t is ⇒ f is ⇒ (iii) when the linear density is increased by switching to another string df dρ 0 and ρ is ⇒ f is ⇒

Lacie kicks a football from ground level at a velocity of 13.9 m/s and at an angle of 25.0° to the ground. how long will the ball be in the air before it lands? how far will the football travel before it lands?