Units and Measurement Questions and Answers

The base unit for gravitational field strength is

Which set is made of units that are not identical?

The unit for $\mu_o$, the permeability of a vacuum is kgms$^{-2}$ and that for $\varepsilon_o$, the permittivity of a vacuum is kg$^{-1}$m$^{-3}$s$^4$. If C is the speed of light in a vacuum, which of the following has units of $\mu_o \varepsilon_o$?

A student used base units to check an equation and found that the left hand side of the equation was equivalent to the right hand side. Which of the following statements about the equation is correct?

Which quantity is not a base quantity?

The base units of Planck's constant are

Which is not a base unit?

Which expression has the newton as its unit?

The relationship between $\alpha$, p, q and t is given by $\alpha = q + pt$ where t is time in seconds. If p has units of $ms^{-1}$ what are the units of q?

The relationship between four physical quantities $x$, $p$, $q$ and $t$ is given by $x = p + qt$, where $t$ is the time in seconds. If $q$ has units of $ms^{-1}$, what are the units of $p$?

Which one has the greatest in magnitude?

In measuring a physical quantity, which statement correctly distinguishes a systematic error from a random error?

A rectangular piece of paper has length 297±1 mm and width 152±1 mm. Using ΔA/A = ΔL/L + ΔW/W, calculate the fractional uncertainty in its area.

A rectangular piece of paper has length 297 mm and width 152 mm. Calculate its area.

What term describes an error that affects every reading in a set of measurements by the same amount and in the same direction?

What term describes an error that causes repeated measurements of the same quantity to have different, unpredictable values?

In an experiment to measure the acceleration of free fall g, a steel ball took 807 ms to fall a distance of 3.20 m from rest. Using s = (1/2)gt^2, calculate the value of g.

In an experiment to find the resistance of an ohmic conductor, current I is plotted against potential difference V. The plotted points lie on both sides of the best fit straight line. Which feature of the graph is evidence that random errors are present?

Current I is plotted against potential difference V for an ohmic conductor. The best fit line is straight, but it cuts the I axis at a positive current when V is zero. Which feature of the graph shows that a systematic error is present?