7. Experimental value of acceleration due to gravity is found to be 9.842 m/s². The accepted value of acceleration due to gravity is
9.81 m/s2. What is the percent error in calculation?
a 0.326 %
b 0.316 %
C 0.981 %
d 0.613 %

Answer : The correct option is, (a) 0.326 %

Explanation :

To calculate the percentage error, we use the equation:

We are given:

Experimental value = 9.842 m/s²

Accepted value = 9.81 m/s²

Now put all the given values in above equation, we get:

Therefore, the percent error in calculation is 0.326 %

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e