Force questions that require Calculations !!!!!!!!!!!

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Force questions that require Calculations !!!!!!!!!!! What fun!

A boy pulls horizontally with a force of 100N on a box of Mass 50kg. Find the resulting acceleration if (a) Force of friction = 0; (b) Force of friction = 25N. + FN - Ffr Fappl + Fg -

A boy pulls horizontally with a force of 100N on a box of Mass 50kg. Find the acceleration motion if (a) Force of friction = 0; (b) Force of friction = 25N. + FN (a) Fx = Fappl – Ffr = ma 100N = (50kg)a a = 2 m/s2 Fy = FN – Fg = ma = 0 (there is no motion or acceleration in the y-direction) - Ffr Fappl + Fg -

A boy pulls horizontally with a force of 100N on a box of Mass 50kg. Find the acceleration motion if (a) Force of friction = 0; (b) Force of friction = 25N. + FN (b) Fx = Fappl – Ffr = ma 100N – 25N = (50kg)a a = 1.5 m/s2 NOTE: Fy = FN – Fg = ma = 0 FN = (50kg)(9.8)=490N (there is no motion or acceleration in the y-direction) - Ffr Fappl + Fg -

A boy pulls at a 30˚ angle with a force of 100N on a box of Mass 50kg. Find the resulting acceleration if force of friction = 0. + FN - Fappl Ffr + Fg -

A boy pulls at a 30˚ angle with a force of 100N on a box of Mass 50kg. Find the resulting acceleration if force of friction = 0. + FN Fx = Fappl cos30 – Ffr = ma 100N cos30 = (50kg)a a = 1.73 m/s2 NOTE: Fy = FN + Fappl sin30 – Fg = ma FN + 100 sin30 – (50)(9.8) = 0 (there is no motion or acceleration in the y-direction) FN = -50 + 490 = 440N - Fappl Ffr + Fg -

A boat is pulled with two forces as shown (one at a 45˚ angle and one at a 37 ˚ angle. Calculate the net force on the boat. + F1 = 40N 45˚ + 37˚ F2 = 30N

A boat is pulled with two forces as shown (one at a 45˚ angle and one at a 37 ˚ angle. Calculate the net force on the boat. + F1x = F1cos45 = 28.3 N F1y = F1sin45 = 28.3N F2x = F2cos37 = 24.0N F2y = F2sin37 = -18.1N Fx = F1x + F2x = 52.3N Fy = F1y + F2y = 10.2N F = (Fx2 + Fy2)1/2 = 53.3N tanΘ = 10.2/52.3 Angle is 11.0˚ F1 = 40N 45˚ + 37˚ F2 = 30N

When a flexible cord pulls on an object (assume the cord has Negligible mass), calculate the acceleration of the system. The Pulling force is 40N and the boxes have a mass of 10kg each. + + FN FN FT FT Fappl + Fg Fg - -

When a flexible cord pulls on an object (assume the cord has Negligible mass), calculate the acceleration of the system. The Pulling force is 40N and the boxes have a mass of 10kg each. + + FN FN FT FT m2 m1 Fappl + NOTE: a is the same for both boxes. a= 2 m/s2 Fg Fg - - Fx=FT=m2a Fx=Fappl - FT=m1a Fappl – m2a = m1a

You are given an Atwood’s Machine. There are two masses hanging from a massless pulley. M1 is 15kg and M2 is 28kg. Calculate acceleration of the masses and the force of tension in the rope. FT FT m2 m1 Fg2 Fg1 - +

You are given an Atwood’s Machine. There are two masses hanging from a massless pulley. M1 is 15kg and M2 is 28kg. Calculate acceleration of the masses and the force of tension in the rope. - + FT FT Fg1 – Fg2 = (m1 + m2)a (15kg)(9.8) – (28)(9.8) = (43kg)(a) m2 m1 NOTE: a is the same for both masses. a= -2.96 m/s2 a is to the left mass. Fg2 Fg1 - + FT – Fg2 = m2a -FT + Fg1 = m1a