Question Library

Which of the following materials does not serve as a safety device in electrical circuits?

You are provided with a stopwatch, a meter rule, a split cork, retort stand and clamp, a pendulum bob, a piece of thread, and other necessary apparatus. i. Place the retort stand on a laboratory stool. Clamp the split cork. ii. Suspend the pendulum bob from the split cork such that the point of support P of the bob is at height H = 100cm above the floor Q. The bob should not touch the floor and H should be kept constant throughout the experiment. iii. Adjust the length of the thread such that the center A of the bob is at a height y= AQ= 20cm from the floor. iv. Displace the bob such that it oscillates in a horizontal plane. v. Take the time t for 20 complete oscillations. vi. Determine the period T of oscillation and evaluate T vii. Repeat the procedure for four other values of y = 30cm, 40cm, 50cm, and 60cm. In each case, determine T and T. viii. Tabulate the results. ix. Plot a graph of T on the vertical axis and y on the horizontal axis, starting both axes from the origin (0,0). x. Determine the slope, s, of the graph and the intercept c on the vertical axis. xi. If in this experiment SR= c, calculate R. x. State two precautions taken to ensure accurate results. (b) i. The bob of a simple pendulum is displaced a small distance from the equilibrium position and then released to perform simple harmonic motion Identify where its: (\(\propto\)) kinetic energy is maximum (\(\beta\)) acceleration is maximum ii. An object of weight 120N vibrates with a period of 4.0s when hung from a spring. Calculate the force per unit length of the spring. [g= 10ms\(^{-2}\), \(\pi\)=3.142]

You are provided with a converging lens and holder, a screen, a ray box containing an illuminated object pin, and a meter rule.(See illustration above) i. Place the lens in its holder such that it is facing a distant object seen through a well-lit laboratory window. Move the screen to and fro until a sharp image of the distant object is formed on it. Measure the distance, \(f_0\), between the screen and the lens. ii. Clamp the meter rule securely to the table. Place the illuminated object pin at the end R of the meter rule. iii. Place the lens at a position P such that X = RP = 20cm. iv. Move the screen to a position Q to receive a sharp image of the object. Measure the distance Y = PQ. v. Evaluate Z = (X+Y) vi. Repeat the procedure for five other values of x = 25cm. 3Ocm, 35cm, 40cm and 45cm. In each case, record X,Y and evaluate Z. vii. Tabulate the results. viii. Plot a graph with Z on the vertical axis and X on the horizontal axis. Draw a smooth curve through the points. ix. Determine from your graph the minimum value of Z=\(Z_0\) and its corresponding distance x. Evaluate W = ½ (\(\frac{Z_0}{4} + \frac{X_0}{2}\)) xi. State two precautions taken to ensure accurate results. (b) i. Draw a ray diagram to show how a Convex lens forms an image of magnification less than one. ii. Name two pairs of features in the human eye and a lens camera that performs similar functions.

You are provided with a battery of e.m.f. E, a key K, a voltmeter, a standard resistor \(R_0\) = 2\(\Omega\), a resistance box R, and some connecting wires. i. Measure and record the e.m.f. E of the battery. i. Set up a circuit as shown in the diagram above with the key open. iii. Set the resistance on the resistance box to R 22. iv. Close the key, read and record the potential difference V on the voltmeter. v. Evaluate V\(^{-1}\) vi. Repeat the procedures for five other values of R = 5\(\Omega\) 10\(\Omega\),12\(\Omega\),15\(\Omega\) and 20\(\Omega\). In each case, record V and evaluate V\(^{-1}\) vii. Tabulate the results. viii. Plot a graph with R on the vertical axis and V\(^{-1}\) l on the horizontal axis, starting both axes from the origin (0,0). ix. Determine the slope, s, of the graph and the intercept c on the vertical axis. x. Calculate \(\propto\) and \(\beta\) from the equations s = \(R_0\) \(\propto\) and c= - (\(R_0\)+B). xi. State two precautions taken to obtain accurate results.

Which of the following is consistent with Charles' law?

You are provided with a battery of e.m.f. E, a key K, a voltmeter, a standard resistor \(R_0\) = 2\(\Omega\), a resistance box R, and some connecting wires. i. Measure and record the e.m.f. E of the battery. i. Set up a circuit as shown in the diagram above with the key open. iii. Set the resistance on the resistance box to R 22. iv. Close the key, read and record the potential difference V on the voltmeter. v. Evaluate V\(^{-1}\) vi. Repeat the procedures for five other values of R = 5\(\Omega\) 10\(\Omega\),12\(\Omega\),15\(\Omega\) and 20\(\Omega\). In each case, record V and evaluate V\(^{-1}\) vii. Tabulate the results. viii. Plot a graph with R on the vertical axis and V\(^{-1}\) l on the horizontal axis, starting both axes from the origin (0,0). ix. Determine the slope, s, of the graph and the intercept c on the vertical axis. x. Calculate \(\propto\) and \(\beta\) from the equations s = \(R_0\) \(\propto\) and c= - (\(R_0\)+B). xi. State two precautions taken to obtain accurate results.

A secondary alkanol can be oxidized to give an?

Which of the following will give a precipitate with an aqueous solution of copper (I) chloride?

The IUPAC name for CH\(_3\)CH\(_2\)COOCH\(_2\)CH\(_3\) is

Hydrocarbons which will react with Tollen's reagent conform to the general formula

The IUPAC name of the compound CF\(_3\)CHBrCl is

A synthetic rubber is not obtained from the polymerization of?

Burning magnesium ribbon in air removes which of the following (i) oxygen (ii) nitrogen (iii) argon and (iv) carbon(iv)oxide?

Which of the following is the best starting material for the preparation of oxygen? Heating of trioxonitrate (v) with

Which of the following metals is the most essential in the regulation of blood volume, blood pressure and osmotic equilibrium?