6. Blanche, a 100 kg shot-putter, is putting the 4 kg shot in a track meet. Just before she releases the shot, Blanche is in the air (her feet are off the ground). At this instant, the only force she exerts against the shot is an 800 N horizontal force directed forward.

a) What is Blanche's horizontal acceleration at this instant?

a) a = 8m/s^2

b) a = 9.8m/s^2

c) a = 200m/s^2

d) a = 9.8m/s^2

Explanation:

Using the laws of newton:

F = ma

where F is the force, m the mass and a the aceleration

a) Solving for the aceleration:

a = F/m

so, replacing the force and the mass of Blanche, we get:

a = 800N/100kg

a = 8m/s^2

b) By the laws of newton, the sumatory of vertical force for Blanche is equal to:

mg = ma

Where g is the gravity

Then, solving for a:

a = g

a = 9.8m/s^2

c) At the same way, solving for the aceleration:

a = F/m

so, replacing the values of the force and the mass of the shot, we get:

a = 800N/4kg

a = 200m/s^2

d) Then, sumatory of vertical force for the shot is equal to:

mg = ma

where g is the gravity

solving for a:

a = g

a = 9.8m/s^2