Precision and Accuracy

Q.

Is arithmetic mean always positive?

Q.

An analytic balance has uncertainty In measurement equal to $\pm$1 mg. Then report the result in terms of percentage if the weight of a compound is
(a) 1 g
(b) 10 g
(c) 100 g

1. $1\pm 0.1\%$;$10\pm 0.01\%;100$ $\pm 0.001\%$

2. $1\pm 0.2\%;10$ $\pm 0.02\%;100$ $\pm 0.002\%$

3. $1\pm 0.1\%;10$ $\pm 0.1\%;100$ $\pm 0.1\%$

4. $1\pm 0.2\%;10$ $\pm 0.2\%;100$ $\pm 0.002\%$

Q.

A round bottom flask is used to store chemicals.

1. True
2. False

Q. Subtract $0.2J$ from $7.26J$ and express the result with correct number of significant figures.

1. $7.1J$
2. $7.06J$
3. $7J$
4. $7.0J$

Q. Which of the following is the most accurate measurement?

1. 9 m
2. 9.0 m
3. 9.00 m
4. 9.000 m

Q. An experiment was conducted by a student and he obtained $3$ values viz. $1.65,1.68$ and $1.71$, during three repetitive trials, respectively. After sometime, the student got the true value, which was $2.37$ So, in the contrast to the real value, the experiments' results should be characterized as:

1. not accurate and not precise
2. accurate but not precise
3. not accurate but precise
4. accurate, precise, but unreliable

Q. The number $0.000043$ is the form of scientific notation should be

1. $4.3\times {10}^{-5}$
2. $4.3\times {10}^4$
3. $4.3\times {10}^5$
4. $4.3\times {10}^6$

Q.

An analytic balance has uncertainty In measurement equal to $\pm$1 mg. Then report the result in terms of percentage if the weight of a compound is
(a) 1 g
(b) 10 g
(c) 100 g

1. ;

2. 

3. 

4. 

Q. The students are given a vernier calipers to measure the outer diameter of a cylinder. The actual outer diameter is 4 cm. The measurements made are given in the following table: $\begin{array}{cccccc}Student& Measurements& & & & \\ & 1& 2& 3& 4& 5\\ A& 4& 4& 4& 4& 4\\ B& 3.5& 3.6& 3.7& 3.8& 3.65\\ C& 3.7& 3.9& 4.1& 4.3& 4\\ D& 3.6& 4.2& 4.4& 4.8& 4.25\\ E& 4.005& 3.995& 4.05& 3.95& 4\end{array}$ In case C, the measurements are said to be:

1. Highly Accurate

2. Highly Precise

3. less precise

4. less accurate

Q.

The students are given a vernier calipers to measure the outer diameter of a cylinder. The actual outer diameter is 4 cm. The measurements made are given in the following table:
$\begin{array}{cccccc}Student& Measurements& & & & \\ & 1& 2& 3& 4& 5\\ A& 4& 4& 4& 4& 4\\ B& 3.5& 3.6& 3.7& 3.8& 3.65\\ C& 3.7& 3.9& 4.1& 4.3& 4\\ D& 3.6& 4.2& 4.4& 4.8& 4.25\\ E& 4.005& 3.995& 4.05& 3.95& 4\end{array}$

1. In case A, the measurements are said to be:

1. Accurate

2. Precise

3. none

4. Both a & b

Q.

In a kingdom there was an excellent archer. The ruler was jealous of his archery skills, so he decided to put his skills to test. The archer was asked to shoot an apple which was placed on his son's head or else his son will be killed. The archer always used his trusted bow.

Case 2: The archer was really confident but the ruler hired a thief to steal his bow and replace it with a defective one which is slightly bent to the side. This time when the archer shot from the new bow he always hit the same spot but slightly deviated from the apple. In this case the archer is:

1. Accurate

2. Precise

3. Both a & b

4. none

Q. A student conducted an experiment and obtained three values during three repetitive trials: $1.65,1.68,1.71$. Later, the student discovered that the true value was $2.37$. In contrast to the real value, the experimental results should be characterized as:

1. not accurate and not precise
2. accurate but not precise
3. not accurate but precise
4. accurate and precise
5. accurate, precise, but unreliable

Q. If the true value for a result is 4.00 cm and a student takes two measurements and reports the result as 3.94 cm and 3.95 cm, then these values are:

1. Precise but are not accurate
2. Precise and accurate
3. Accurate but not precise
4. Neither accurate nor precise

Q.

The students are given a vernier calipers to measure the outer diameter of a cylinder. The actual outer diameter is 4 cm. The measurements made are given in the following table:
$\begin{array}{cccccc}Student& Measurements& & & & \\ & 1& 2& 3& 4& 5\\ A& 4& 4& 4& 4& 4\\ B& 3.5& 3.6& 3.7& 3.8& 3.65\\ C& 3.7& 3.9& 4.1& 4.3& 4\\ D& 3.6& 4.2& 4.4& 4.8& 4.25\\ E& 4.005& 3.995& 4.05& 3.95& 4\end{array}$

In case B, the measurements are said to be:

1. Highly Accurate

2. Highly Precise

3. Both a & b

4. none

Q.

In a kingdom there was an excellent archer. The ruler was jealous of his archery skills, so he decided to put his skills to test. The archer was asked to shoot an apple which was placed on his son's head or else his son will be killed. The archer always used his trusted bow.

Now that his son's life was in his hands the archer's hand started to tremble. So, now when he started shooting with the original bow he hit different spots which were close to the apple. In this case the archer is:

1. Accurate

2. Precise

3. none

4. Both a & b

Q. Which of the following options is not correct?

1. $2.300+0.02017+0.02015=2.340$
2. $126,000$ has $3$ significant figures
3. $15.15\mu s=1.515\times {10}^{-5}s$
4. $0.0048=48\times {10}^{-3}$

Q.

Without looking at the relevant text, convert$30cm$ to feet, expressed as the nearest whole number. (Look at a long ruler to find out!) Based on this, say roughly how many feet make up a meter.

Q. Two student performed the same experiment separately and each one of them recorded two readings of mass which are given below. Correct reading of mass is $3.0g$. One the basis of given data, mark the correct option out of the following statement.

Student	Reading
$A$	$3.012.99$
$B$	$3.052.95$

1. Results of both the students are neither accurate nor precise.
2. Results of students $A$ are both precise and accurate.
3. Results of students $B$ are neither precise and nor accurate.
4. Results of students $B$ are both precise and accurate.

Q. If repeated measurements give values close to one another, the number is:

1. surely precise
2. surely accurate
3. surely precise and accurate
4. all of these are correct

Q.

In a kingdom there was an excellent archer. The ruler was jealous of his archery skills, so he decided to put his skills to test. The archer was asked to shoot an apple which was placed on his son's head or else his son will be killed. The archer always used his trusted bow.

Case 2: The archer was really confident but the ruler hired a thief to steal his bow and replace it with a defective one which is slightly bent to the side. This time when the archer shot from the new bow he always hit the same spot but slightly deviated from the apple. In this case the archer is:

1. Precise

2. Both a & b

3. Accurate

4. none

Q.

In a kingdom there was an excellent archer. The ruler was jealous of his archery skills, so he decided to put his skills to test. The archer was asked to shoot an apple which was placed on his son's head or else his son will be killed. The archer always used his trusted bow.

Case 1: In practice shots he always hits the apple. In this case the archer is:

1. none

2. Accurate

3. Precise

4. Both a & b

Q. A student conducted an experiment and obtained three values during three repetitive trials: 1.65, 1.68, 1.71. Later, the student discovered that the true value was 2.37. In contrast to the real value, the experimental results should be characterized as:

1. not accurate and not precise
2. accurate and precise
3. accurate but not precise
4. accurate, precise, but unrealiable
5. not accurate but precise

Q. Two samples were weighed using different balance and the following data were obtained.
Sample #1=3.719 grams
Sample #2=0.42 gram
The total mass of the samples should be reported as :

1. 4 grams
2. 4.139 grams
3. 4.140 grams
4. 4.14 grams
5. 4.1 grams