Transcript 16 Test Review ppt! - Goshen Community Schools

Test Review
Chapters 12-16
Relativity
Question #1
What happens to the
gravitational force when 2
objects get farther away
from each other?
Gm1m2
F
2
d
It decreases!
Question #2
A 35 kg rock and a 250 kg rock
are placed 17 m apart. What
is the gravitational force
between them?
Gm1m2
F
2
d
11
(6.67 x10 )(35)( 250)
F
2
17
9
F  2.0 x10 N
Question #3
How fast must a
spaceship travel to
be able to leave
the earth’s
gravitational pull?
8 km/s
Question #4
How long does it take
light from the sun to
travel to Earth?
8 minutes
Question #5
How much energy is
contained within a T-84
calculator with a mass
of 0.89 kg?
E  mc
2
E  (.89)(3.00 x10 )
8 2
E  (.89)(9.00 x10 )
16
E  8.0 x10 J
16
Question #6
The sun exerts a 3.5 x 1022 N force
on the earth.
What is the distance between the
1.99 x 1030 kg sun and the
5.97 x 1024 kg Earth?
Gm1m2
F
2
d
30
24
)(1.99 x10 )(5.97 x10 )
3.5 x10 
2
d
22 2
11
30
24
3.5 x10 d  (6.67 x10 )(1.99 x10 )(5.97 x10 )
22
(6.67 x10
11
11
30
24
(6.67 x10 )(1.99 x10 )(5.97 x10 )
d 
22
3.5 x10
2
22
d  2.26 x10
2
d  1.5 x10 m
11
Question 7
In Feb. 2007, the Hubble Telescope
captured pictures of a dying star with
a mass of 2.0 x 1030 kg..
If this star was 4,200 light years away,
how long ago did the star die?
~ 4,200 years ago
Question #8
At what point during the planet’s
orbit around the sun does it have
the least amount of velocity?
S
Question #9
What is the
speed of light?
(in m/s)
?
3.00 x
8
10 m/s
Question #10
What is the gravitational force
5
between a 7.5 x 10 kg object
and a 2.50 x 108 kg object
11
that are 2.5 x 10 m apart?
Gm1m2
F
2
d
11
5
8
(6.67 x10 )(7.5 x10 )( 2.50 x10 )
F
11 2
(2.5 x10 )
F  2.0 x10
19
N
Question #11
2 objects are attracted to
each other.
What happens to their speed
as they get closer?
It increases!
Question #12
What were black holes
before they became
black holes?
Stars!
Question #13
Name 2 points during the planet’s
orbit around the sun where it has
the same amount of velocity.
All below are correct…
P&V
Q&U
R&T
Question #14
If our sun were to become a
black hole tomorrow, what
would happen to the earth’s
orbit around the sun?
Nothing.
…because our orbit is due to the gravitation
between the sun & the earth, and that
didn’t change simply because the sun
became a black hole.
A black hole is the same mass, but in a
much smaller package!
The end.