A lamp hangs vertically from a cord in a descending elevator that decelerates at 2.9 m/s2. (a) If the tension in the cord is 86 N, what is the lamp's mass? (b) What is the cord's tension when the elevator ascends with an upward acceleration of 2.9 m/s2?

The mass of the lamp is 6.77 kg and tension in the cord is 85.97 N.

Explanation:

Given that,

A lamp hangs vertically from a cord in a descending elevator that decelerates at

(a) We need to find the mass of the lamp if the tension in the cord is 86 N.

When the elevator is descending. The net force acting on it is given by :

(2) Let T is the cord's tension when the elevator ascends with an upward acceleration of .

So,

So, the mass of the lamp is 6.77 kg and tension in the cord is 85.97 N. Hence, this is the required solution.

  1.the balanced   chemical equation is as below

cu +   2 ag(no)₃ → cu(no₃)₂   +2 ag

2.the   much silver   produced   is   50.9 g

step 1: find the   moles of cu

moles =   mass÷   molar mass

  from periodic table the molar mass of cu = 63.5 g/mol

moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236   moles

step 2: use the mole ratio to determine the   moles of ag

from equation above   cu: ag   is 1: 2

therefore the moles of ag   =0.236   moles   x 2/1 =0.472   moles

step 3: find the mass   of ag

mass = moles x molar mass

from periodic table   the molar mass of ag =107.87 g/mol

mass   = 0.472   moles x 107.87 g/mol = 50.9 g

3.   the   much   silver   collected worth is   1.797 oz

  convert   50.9 g   to oz

that is   1 gram = 0.0353 oz

          50.9 grams =?   oz

by cross multiplication

={(50.9 grams x 0.0353 oz) / 1   gram}   =1.797 oz