The weight of a piece of wire is directly proportional to its length. a piece of wire is 25cm long and has a weight of 6 grams. another piece of the same wire is 30cm long. calculate the weight of the 30cm piece of wire p is inversely proportional to m. p=48 when m=9 calculate the value of p when m =12.

Part A

Weight of a piece of wire is directly proportional to its length

⇒ Weight of wire piece (W) α Length of wire (L)

⇒ W = k × L

When L = 25 cm, then W = 6 gms

⇒ = k

⇒ k =

To calculate weight of 30 cm wire, put value of k and W in the expression W = k × L

⇒ W = × 30

⇒ W = 7.2 gms

Part B

p α m

⇒ p = k × m

If p=48 and m=9

k =

⇒ k =  

Now to calculate p when m = 12, substitute the value of m and k in p = k × m

p = × 12

⇒ p = 64

step-by-step explanation:

we can use this expression to calculate the energy gain as a particle moves with a field or the energy loss as it moves against it. (note that it is also used to define the electron-volt, a unit of energy equal to that gained by an electron as it falls through a pd of 1 v, i.e. w = 1 ev = 1.6 10-19 c 1 v = 1.6 10-19j).in fact this expression is really nothing more than the statement that potential is the potential energy per unit charge. in this case, v= w/qis simply stating that the change in potential energy(or work done) per unit charge is equal to the change in potential (or potential difference), v.student questions: uniform electric fields2electron beamcathode+5 kvanode0 v