Element 5 - Science T levels

Derived units are obtained from various combinations of

• Base units.

• International standards.

• Electrical quantities.

• Metric prefixes.

An unconstrained steel bar is cooled from a temperature of 450 °C to 30 °C. How will this affect the length of the bar?

• The length will reduce.

• The length will stay the same.

• The length will increase.

• The length will increase then reduce.

Calculate the quantity of latent heat required to melt 15 kg of steel at its melting point.

• 63 kJ.

• 280 kJ.

• 42 MJ.

• 63 MJ.

What are the units of pressure?

• N m⁻².

• m s⁻².

• N m.

• kg m⁻³.

Which of the following is a scalar quantity in engineering mechanics?

• Displacement.

• Speed.

• Velocity.

• Acceleration.

6.2 × 10⁹ seconds is equivalent to:

• 6.2 teraseconds.

• 6.2 picoseconds.

• 6.2 nanoseconds.

• 6.2 gigaseconds.

The degree of closeness of the measured value of a certain quantity with its true value is known as:

• Accuracy.

• Precision.

• Tolerance.

• Sensitivity.

Which of the following is used to check the diameters of holes?

• Ring gauge.

• Slip gauge.

• Plug gauge.

• Standard screw pitch gauge.

Which two particles make up the nucleus of an atom?

• Protons and electrons.

• Protons and neutrons.

• Molecules and compounds.

• Neutrons and electrons.

Which of the following contains only one type of atom?

• Compound.

• Molecule.

• Element.

• Solution.