This is from educake but for a certain spring, k = 15n/m. a weight is hung from the spring, stretching it from 0.3m to 0.4m. what force did the weight produce ? what is the name of the force

k = spring constant of the spring = 15 N/m

x₀ = initial position of the spring = 0.3 m

x = final position of the spring = 0.4 m

Δx = stretch in the spring

stretch in the spring is given as

Δx = x - x₀

Δx = 0.4 - 0.3

Δx = 0.1 m

the spring force balances the weight

hence

F = force by the weight

using equilibrium of force in vertical direction

force by weight = spring force

F = k  Δx

inserting the values

F = 15 x 0.1

F = 1.5 N

the force by weight is also known as force of gravity.

c)as speed changes, wavelength and frequency change.

everything changes!

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂