Mechanics

An ornament weighing 36g in air, weighs only 34g in water. Assuming that some copper is mixed with gold to prepare the ornament, find the amount of copper in it. Specific gravity of gold is 19.3and that of copper is 8.9.

Karan Pandey

13 Years agoGrade

2 Answers

naveen kumar

13 Years ago

mass of ornament in air=36gm - 1 mass of ornament in water=34gm

desity of gold=19.3gm/cc density of copper is 8.9gm/cc

loss of wt=wt of displaced water

36-34=2gm

so, v*p*g=2*g

v=v of gold+v of copper

volume=mass/density

mass of gold/19.3 + mass of copper/8.9 * 1= 2

8.9mass gold + 19.3 mass of copper= 2*19.3*8.9=343.54 - 2

from equations i and 2

m of copper=2.225gm

ankit singh

6 Years ago

mass of ornament in air=36gm - 1 mass of ornament in water=34gm

desity of gold=19.3gm/cc density of copper is 8.9gm/cc

loss of wt=wt of displaced water

36-34=2gm

so, v*p*g=2*g

v=v of gold+v of copper

volume=mass/density

mass of gold/19.3 + mass of copper/8.9 * 1= 2

8.9mass gold + 19.3 mass of copper= 2*19.3*8.9=343.54 - 2

from equations i and 2

m of copper=2.225gm

Three identical balls are placed on a frictionless horizontal surface touching each other. They stick to each other because of adhesive. Another ball of same radius and mass m is placed over the void created by the three balls. Find the forces applied by the balls kept on the floor to each other if the system remains in equilibrium.

mechanics

1 Answer Available

Last Activity: 10 Months ago

A car loaded with water having total mass 1000 kg moves on a straight horizontal Road starting from rest under the action of a force of 100 Newton. The water spills throw a small hole in the bottom at a rate of 0.1 KG per second the velocity of cart after 300 seconds is nearly.

11
21
31
41

mechanics

1 Answer Available

Last Activity: 10 Months ago

A metal strip clamped at one end vibrates with a frequency of 20 Hz and amplitude of 5 mm
at the free end, where a small mass of 2 g is positioned. determine
(i) The velocity of the end when passing through the zero position
(ii) The acceleration at maximum displacement
(iii) The maximum kinetic energy of the mass

mechanics

2 Answers Available

Last Activity: 3 Years ago

An object of mass m = 0.25 kg oscillates in a fluid at the end of a vertical spring of spring
constant kH = 85 N/m, see Fig.1. The effect of the fluid resistance is governed by the
damping constant b = 0.07kg/s.
(i) Find the period of the damped oscillation.
(ii) By what percentage does the amplitude of the oscillation decrease in each cycle?

mechanics

1 Answer Available

Last Activity: 3 Years ago

If a=x² find the displacement at t =3sec if body velocity at t= 0 sec is 0

mechanics

1 Answer Available

Last Activity: 3 Years ago

View all Questions

An ornament weighing 36g in air, weighs only 34g in water. Assuming that some copper is mixed with gold to prepare the ornament, find the amount of copper in it. Specific gravity of gold is 19.3and that of copper is 8.9.

Karan Pandey

2 Answers

naveen kumar

ankit singh

Other Related Questions on mechanics

A car loaded with water having total mass 1000 kg moves on a straight horizontal Road starting from rest under the action of a force of 100 Newton. The water spills throw a small hole in the bottom at a rate of 0.1 KG per second the velocity of cart after 300 seconds is nearly.11213141

If a=x² find the displacement at t =3sec if body velocity at t= 0 sec is 0

A car loaded with water having total mass 1000 kg moves on a straight horizontal Road starting from rest under the action of a force of 100 Newton. The water spills throw a small hole in the bottom at a rate of 0.1 KG per second the velocity of cart after 300 seconds is nearly.

11
21
31
41