Formulas

m/s $s=d/t$ speed = distance [m] / time [s]
m/s² $a= v-u / ∆t$
acceleration (1) = ∆ velocity [m/s] / ∆ time [s]
N/kg $g=W/m$
gravitational field strength = force [N] / mass [kg]
N $W=m*g$
weight or force = mass [kg] x gravitational field strength [N/kg]
kg/m³ $p=m/V$ density = mass [kg] / volume [m³]
N/m $k=F/x$ spring constant = force [N] / extension of the spring from its original state [m]
N $F = m*a$ resultant force (1) = mass [kg] x acceleration [m/s²]
N $a=F/m$ aceleration (2) = resultant force [m/s²] / mass [kg]
Nm $M=F*d$ moment = force [N] x perpendicular distance from the pivot [m]
Ns or kg m/s $p=m*v$ momentum = mass [kg] x velocity [m/s]
Ns or kg m/s $p=F*t$ impulse = force [N] x time [s]
N $F=∆p/∆t$ resultant force (2) = ∆ momentum [Ns or kg m/s] / ∆ time [s]
Nm or J $KE=(mv^2)/2$ kinetic energy = ( mass [kg] x velocity² [m/s] ) / 2
Nm or J $GPE=mg ∆h$ gravitational potential energy = mass [kg] x gravitational field strength [N/kg] x ∆ height [m]
Nm or J $W=F*d$ work = force [N] x distance [m]
W $P=W/t$ power = work [Nm or J] / time [s]
N/m² or Pa $P=F/A$ pressure (1) = force [N] / area [m²]
N/m² or Pa $P=pg∆h$ pressure (2) = density [kg/m³] x gravirational field strength [N/kg] x height [m]
Efficiency % $\frac{useful.output}{total.input} * 100$ percentage of efficiency (1) = ( useful energy output / total energy input ) x 100
percentage of efficiency (2) = ( useful power output / total power input ) x 100
percentage of efficiency (3) = ( useful work output / total work input ) x 100

Measuring Equipments

For Volume

A measuring cylinder can be used to determine the volume of an irregular shape.

Or displacement can.

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For Length

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  1. Volume: Displacement Can / Measuring Cylinder
  2. Time: Stopwatch / Timer
  3. Length: Ruler / Measuring Tape / Vernier Callipers (.01) / Micrometer screw gauge (.001cm)

Errors in Physics

  1. Zero Error: Caused by faulty equipment that doesn’t reset to zero property. For example, a stopwatch that has not been resetted to zero before use, can give a zero error. To minimise, calibrate the instrument before use.
  2. Parallax Error: Occur during measurement, such as inocerrect position of the eye or when the object is not touching the marking of the scale — there is a gap. Eye should be at a perpendicular angle to the scale for avoiding parallax error. And ensure that the object is in contact with the scale. For example, a measuring cylinder should be measured by viewing the bottom of the meniscus at eye level or perpendicular angle while putting the measuring cylinder on a smooth surface.

Scalar vs Vector

Scalar Quantity → Magnitude only (e.g. Volume, Distance, Speed, Time, Mass, Energy, Temp.)

Vector Quantity → Direction and Magnitude (e.g. Force, Weight, Velocity, Acceleration, Momentum, Electric Field Strength, Gravitational Field Strength.)

Resultant Force / Vector