Hello!
The quickest and simplest way would be to take it to a jeweler or pawn shop and get it checked.
However, another way is: make a light, tiny scratch on the item using a small nail file or similar rough object. Choose a spot that is not noticeable if you want to keep it's value. apply a small drop of nitric acid to the scratch (use a dropper if you have one)
If there is no reaction, then the piece is probably made from real gold
I hope this helps, and have a nice day!
Answer:
Explanation:
x = < 20, 7, -1 > m
y = < 25, 9, - 5> m
t = 0.1 s
Displacement between x and y is given by
z = y - x
z = < 25 - 20, 9 - 7, - 5 + 1>
z = < 5, 2, - 4 >
Magnitude of displacement is given by
= 6.71 m
Average velocity = total displacement / total time = 6.71 / 0.1 = 67.1 m/s
Answer:
t=0.704s
Explanation:
A child is running his 46.1 g toy car down a ramp. The ramp is 1.73 m long and forms a 40.5° angle with the flat ground. How long will it take the car to reach the bottom of the ramp if there is no friction?
from newton equation of motion , we look for the y component of the speed and look for the x component of the speed. we can then find the resultant of the speed
Vy^2=0+2*9.8*1.73sin40.5
Vy^2=22.021
Vy=4.69m/s
Vx^2=u^2+2*9.81*cos40.5
Vy^2=25.81
Vy=5.08m/s
V=(Vy^2+Vx^2)^0.5
V=47.71^0.5
V=6.9m/s
from newtons equation of motion we know that force applied is directly proportional to the rate of change in momentum on a body.
f=force applied
v=velocity final
u=initial velocity
m=mass of the toy, 0.046
f=ma
f=m(v-u)/t
v=u+at
6.9=0+9.8t
t=6.9/9.81
t=0.704s
Answer:
potential energy decreases
kinetic energy increases