Answer and Explanation
Arranging the measured values in increasing order;
4.3s, 4.6s, 4.6s, 4.8s, 5.1s, 5.8s
The two outliers are obviously 4.3s and 5.8s; An outlier is a value in a statistical sample which does not fit a pattern that describes most other data point. Outliers make the average value complicated. So, it is usually better for data to be precise with data points spreading out around a small area.
So, the mean is the average of the four remaining data points after removing the outliers.
Mean = (4.6 + 4.6 + 4.8 + 5.1)/4
Mean = 4.775s
So, the value recorded should be 4.775s, 4.78s or 4.8s depending on the number of decimal places allowed.
QED!
The answer is C, has negative acceleration.
It will act upon a buoyant force on the magnitude of which is equal to weight of the fluid
the water specific heat will remain at 4.184.
Here in this case we can use work energy theorem
As per work energy theorem
Work done by all forces = Change in kinetic Energy of the object
Total kinetic energy of the solid sphere is ZERO initially as it is given at rest.
Final total kinetic energy is sum of rotational kinetic energy and translational kinetic energy

also we know that


Now kinetic energy is given by





Now by work energy theorem
Work done = 10500 - 0 = 10500 J
So in the above case work done on sphere is 10500 J