A500-kg elevator is raised to a height of 20 m in 10 seconds. calculate the power of the motor. a) 98,000 w b) 9,800 w c) 2,500 w d) 1000 w

<>"power = 500 kg x 9.8 m/s² x 20 m / 10s = 9800 watts."<>

Power, P =9800 W

Explanation:

It is given that,

Mass of the elevator, m = 500kg

It is raised to a height of 20 m in 10 seconds

Power is defined as the work done per unit time.

Work done is given by :

h is the height

So,

P = 9800 Watts

Hence, the power of the motor is 9800 W. The correct option is (b).

  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

the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.