Physical Science Formulas

Question 1

Speed

Answer 1

v = d / (t₂-t₁)

v is speed

d is distance

(t₂ - t₁) is change of time

Question 2

Velocity

Answer 2

V = d / (t₂-t₁)

V is velocity, it is a vector quantity

d is displacement (net distance and direction of motion)

(t₂-t₁) is change in time

Question 3

Acceleration

Answer 3

a = (v₂ - v₁) / (t₁ - t₂)

acceleration (a) = change in speed(v₂ - v₁) / time interval (t₁ - t₂)

May apply to a change in a scalar (a) or vector (a).

Question 4

Distance travelled in a free fall

Answer 4

d=1/2g(t₂-t₁)²

d is distance in free fall

g is gravitational acceleration (9.81N)

t₂-t₁ is time interval since the beginning of the free fall

Question 5

Law of universal gravitation

Answer 5

F_g= G ((M*m) / r²)

F_gis the gravitational force on a system

G is the universal gravitational constant (9.81N)

M is the mass of the 1st object

m is the mass of the system or second object

r is the radial distance between the centers of M and m

Question 6

Linear momentum

Answer 6

p=mv

p is the momentum of a system

m is the sytem’s mass

v is its linear speed

Question 7

Newton’s 2nd Law

Answer 7

F = ma

F is the net force on a system

m is mass

a is acceleration

Question 8

Speed in a free fall

Answer 8

v = g(t₂-t₁)

v is speed of object in free fall

g is the gravitational acceleration

t₂-t₁time interval from the start of free fall

Question 9

Weight

Answer 9

w = mg

w is weight (vector force)

m is mass (kg)

g is local gravitational acceleration (9.81 N/kg)

At earth’s surface 1kg = 9.81 Newtons (N)