An indestructible bullet 2.00 cm long is fi red straight through a board that is 10.0 cm thick. The bullet strikes the board with a speed of 420 m/s and emerges with a speed of 280 m/s. (a) What is the average acceleration of the bullet through the board? (b) What is the total time that the bullet is in contact with the board? (c) What thickness of board (calculated to 0.1 cm) would it take to stop the bullet, assuming the acceleration through all boards is the same?

To Test the Value of Gravitational Acceleration at Earth’s Surface Mennum Subba Saint Cloud State University Abstract When the object is freely falling under the influence of gravity, it is freefall. This experiment is done to calculate the value of gravitational acceleration on a body at earth’s surface under the interval of time with the same frequency.Acceleration due to gravity is not affected by mass, shape, position, temperature and pressure but affected by air resistance and other external forces. We calculated the mean value of acceleration due gravity or freefall as 974.1783 cm/s and its standard deviation is 0.8436567 cm/s and an error analysis of 0.59405102%. Therefore, we calculated the acceleration due to gravity on an object which had a littl