Question 4641:

• NECO 2009

The work done in extending a spring by 40 mm is 1.52J. Calculate the elastic constant of the spring.

A. 38.8 Nm^-1
B. 60.8 Nm^-1
C. 190.0 Nm^-1
D. 1900.0 Nm^-1
E. 3800.0 Nm^-1

Question 4642:

• NECO 2009

Which of the following statements is correct about volatile liquids? They have ____________

A. Low boiling point
B. Low evaporating rate
C. High conductivity
D. High density
E. High viscosity

Question 4643:

• NECO 2009

Two images Y and X are formed by a plane mirror and a convex mirror respectively. Which of the following is correct about their characteristics?

A. Both are inverted
B. The magnification of Y is greater than one while that of X is one
C. The magnification of Y is one while that of X is less than one
D. Y is inverted while X is erect
E. Y is real while X is virtual.

Question 4644:

An element and its isotopes differ only in the number of ____________

A. Electrons
B. Neutrons
C. Protons
D. Irons

Question 4645:

Complete the following sentence: When electrons from a heated filament accelerate through vacuum toward a positive plate,

A. Only an electric field will be produced.
B. Only a magnetic field will be produced.
C. Electromagnetic waves will be produced.
D. Longitudinal waves will be produced.