OC userin Physics·9 Nov 2017Q5.9 A crate slides up an inclined ramp and then slides down the ramp after momentarily stopping near the top. There is kinetic friction between the surface of the ramp and the crate. Which is greater? () The crate's acceleration going up the ramp; (ii) the crate's acceleration going down the ramp; (iii) both are the same. Explain.
OC userin Physics·9 Nov 2017Figure E5.8 5.8 A 1130-kg car is held in place by a light cable on a very smooth (frictionless) ramp (Fig. E5.8). The cable makes an angle of 31.0° above the sur- face of the ramp, and the ramp itself rises at 25.0° above the horizontal. (a) Draw a free-body diagram for the car. (b) Find the tension in the cable. (c) How hard does the surface of the ramp push on the car? 25.00
OC userin Chemistry·9 Nov 201776. Consider the reaction: 12(g) + Cl2(g) = 2 ICI(g) Kp = 81.9 at 25°C Calculate AGxn for the reaction at 25°C under each of the following conditions: a. standard conditions b. at equilibrium c. Pa = 2.55 atm; R = 0.325 atm; Pa, = 0.221 atm
OC userin Physics·11 Nov 201731.13" A150-resistor is connected in series with a 0.250-H inductor and an ac source. The voltage across the resistor is UR = (3.80 V)cos[(720 rad/s)t]. (a) Derive an expression for the circuit current. (b) Determine the inductive reactance of the inductor. (c) Derive an expression for the voltage UL across the inductor.
OC userin Chemistry·9 Nov 20175. What is the pH of a buffer solution when the concentrations of both buffer components (the weak acid and its conjugate base) are equal? What happens to the pH when the buffer contains more of the weak acid than the conjugate base? More of the con- jugate base than the weak acid?
OC userin Physics·9 Nov 201714.8. In a physics lab, you attach a 0.200-kg air-track glider to the end of an ideal spring of negligible mass and start it oscillating. The elapsed time from when the glider first moves through the equilibrium point to the second time it moves through that point is 2.60 s. Find the spring's force constant.
OC userin Chemistry·8 Nov 201739. Give each ionic compound an appropriate name. a. Sno b. Cr,S3 C. RbI d. BaBr2
OC userin Chemistry·10 Nov 2017104. Consider the reaction shown here occurring at 25°C. Cr(s) + Cd2+(aq) — Cr2+(aq) + Cd(s) Determine Ecell, K, and AGxn for the reaction and complete the table. [Cd2+1 [Cr2+1 Q Ecoll A Grxn 1.00 1.00 1.00 x 10-5 1.00 x 10-5 1.00 4.18 x 10-4 1.00 1.00
OC userin Physics·8 Nov 201731.11 - A 0.180-H inductor is connected in series with a 90.0-12 resistor and an ac source. The voltage across the inductor is v. = -(12.0 V)sin((480 rad/s)t]. a) Derive an expression for the voltage Ur across the resistor. (b) What is up at t = 2.00 ms?
OC userin Chemistry·7 Nov 201759. Methanol (CH3OH) burns in oxygen to form carbon dioxide and water. Write a balanced equation for the combustion of liq- uid methanol and calculate AHIX, A Sex, and A Gixnat 25 °C. Is the combustion of methanol spontaneous?
OC userin Physics·9 Nov 20172.36 A small rock is thrown vertically upward with a speed of 22.0 m/s from the edge of the roof of a 30.0-m-tall building. The rock doesn't hit the building on its way back down and lands on the street below. Ignore air resistance. (a) What is the speed of the rock just before it hits the street? (b) How much time elapses from when the rock is thrown until it hits the street?
OC userin Chemistry·9 Nov 2017104. Predict whether a precipitate will form if you mix 175.0 mL of a 0.0055 M KCl solution with 145.0 mL of a 0.0015 M AgNO3 solution. Identify the precipitate, if any.
OC userin Chemistry·7 Nov 201729. How much time (in seconds) does it take light in a vacuum to travel 1.00 billion km? a) 3.00 x 1017 b) 3.33 s c) 3.33 x 10's d) 3.00 x 1020
OC userin Chemistry·6 Nov 201763. The rate constant (k) for a reaction was measured as a function of temperature. A plot of In k versus 1/T in K) is linear and has a slope of -7445 K. Calculate the activation energy for the reac- tion.
OC userin Chemistry·9 Nov 201721. What is the structure of benzene? What are the different ways in which this structure is represented?