Which of the following statements is CORRECT about the earth's magnetic field?

• A. the angle of dip is the angle which a freely suspended magnet makes with the vertical
• B. the angle of declination is the angle between the magnetic meridian and the geographic meridian
• C. the angle of declination is the angle which a magnetic compass makes with the magnetic meridian
• D. the angle of inclination is the difference between the angle of dip and the angle of declination

which of the following statements are TRUE of isotopes? i. isotopes of an element have the same chemical properties because they have the same number of electrons. ii. isotopes of elements are normally separated using physical properties. iii. isotopes of an element have the same number of protons in their nuclei.

• A. i and ii only
• B. i and iii only
• C. ii and iii only
• D. i, ii, and iii

An insulated rod when rubbed with a material acquires

• A. a negative charge if it is made of glass and rubbed with silk
• B. no charge if it is made of glass and rubbed with fur
• C. no charge if it is made of copper and rubbed with silk
• D. a positive charge if it is made of copper and rubbed with fur

To convert an alternating current dynamo into a direct current dynamo, the

• A. number of turns in the coil is increased
• B. strength of the field magnet is increased
• C. slip rings are replaced with a split ring commutator
• D. coil is wound on a soft iron armature

A spring of force constant 1500Nm^-1 is acted upon by a constant force of 75N. Calculate the potential energy stored in the string

• A. 1.9J
• B. 2.8J
• C. 3.45J
• D. 0.43J

The function of the system of granulated carbon mixed with manganese (IV) oxide in a Letanche cell is to

• A. increase the e.m.f. of the cell to 2.0V
• B. prevent local action in the cell
• C. prevent polarisation in the cell
• D. make the cell black and hence a good radiator

A body of weight W N rest on a smooth plane inclined at an angle\(\theta\)^o to the horizontal. What is the resolved part of the weight in Newtons along the plane?

• A. W sin\(\theta\)
• B. W cos\(\theta\)
• C. W sec\(\theta\)
• D. W tan\(\theta\)

Which of the following obeys Ohm's Law?

• A. Glass
• B. Diode
• C. All electrolytes
• D. All metals

In a ray diagram for a thin converging lens, a ray that is not parallel to the optic axis but passes through the optic center will

• A. pass through undeviated
• B. pass through the center of curvature after refraction
• C. emerge parallel to the principal axis
• D. pass through the principal focus after refraction

Find the tension T1 in the diagram below if the system is in equilibrium

[G = 10ms^-2]

• A. 200/√3N
• B. 100/√3N
• C. 300/√3N
• D. 100N