I need them worked out and answered. Thanks alot! 1. To be a scientific hypothes
ID: 1307408 • Letter: I
Question
I need them worked out and answered. Thanks alot!
1. To be a scientific hypothesis requires that the statement be
a) testable, true or false
b) convincing
c) testable, true
d) true
e) compatible with existing theories
2. Consider the following: 1) Atoms are the smallest units of matter; 2) Space is filled with an undetectable substance; 3) There is intelligent extraterrestrial life somewhere in the universe. Of these three, the ones that are scientific hypotheses today is/are
a) none of them b) 1 c) 2 d) 3 e) 1 and 3
3. A ball rolls off a table of height 1 m at a
horizontal speed of 20 m/s. When it hits the
ground, at what angle (below horizontal) does it hit?
a) 12o b) 23o c) 35o d) 47o e) 59o
4. A mass (5 kg) hangs at rest
from the left side of an Atwoods
machine. On the right side is
a mass of 10 kg. The pulley is
mass-less and frictionless.
The cord is mass-less and
stretch-free. How fast does
the right-hand mass fall
downward when it has fallen 1 m?
5. A block with mass 20 kg is sliding up a
plane (coefficient of friction 0.2, inclined
at 20o) at a speed of 2 m/s to the right
(positive x-direction). How far does it go
up along the plane before it comes to rest
momentarily?
a) 0.2 m b) 0.4 m c) 1.0 m d) 1.5 m e) 2.0 m
6. Given the vectors and . Consider . What is the angle between this resulting sum and the positive x-axis?
a) 5o b) 10o c) 15o d) 20o e) 25o
7. Given the initial velocity m/s of a moving object. It is subject to the acceleration m/s2 for a period of 3 seconds. What is the objects final speed?
8. A mass (10 kg) rests on a surface
(mstatic=0.6) connected by a cord to
a hanging mass of 2 kg. The
connecting cord is mass-less and
stretch-free. The pulley is mass-less
and frictionless. What is the
acceleration of the heavier mass?
a) 0 kg m/s2 b) 1.1 kg m/s2 c) 2.2 kg m/s2 d) 3.3 kg m/s2 e) 4.9 kg m/s2
9. A block is sliding to the right up an inclined plane (10o) at an initial speed of 0.5 m/s. The coefficient of kinetic friction is 0.3. The block stops momentarily. If it does not slide back down, how large must the minimum coefficient of static friction be?
a) 0.1 b) 0.15 c) 0.2 d) 0.25 e) 0.3
10. If a ball rolls off of a table top (horizontal velocity only), it reaches the ground in 0.2 seconds. How high was the table?
a) depends on horizontal speed b) 0.20 m c) 0.44 m d) 0.59 m e) impossible to tell
11. A cannon is fired at 45o above the horizontal with a muzzle velocity of 30 m/s. The cannon is firing from ground level and the field is level. How far down field does the cannon ball strike the ground? a) 79 m b) 92 m c) 107 m d) 130 m e) 149 m
12. A cannon fires up at an angle of 70o above
the horizontal with a muzzle velocity of 30 m/s.
What is the maximum height above the cannon
reached by the cannon ball?
a) 20m b) 25m c) 30m d) 40m e) 50m
13. A car comes around a corner on a flat surface.
The turn has a radius of curvature of 50 m. The
surface and the tires have a coefficient of friction
of 0.2. At what maximum speed can a car
come around this corner without slipping?
a) 5 m/s b) 8 m/s c) 12 m/s d) 15 m/s e) 20 m/s
14. A cannon fires a cannon ball from the wall of
a castle. The muzzle velocity of the gun is 40 m/s.
The cannon fires upward 25o above the horizontal.
The cannon ball strikes the level ground below 4 s
after being fired. How high was the cannon?
a) 0 m b) 4 m c) 7 m d) 11 m e) 14 m
15. A car comes around a banked curve (q=20o),
radius 75 m, coefficient of friction 0.4. At what
maximum speed can the car make it around
the corner without sliding?
a) 18 m/s b) 24 m/s c) 28 m/s d) 32 m/s e) 36 m/s
16. Aunt Matilda goes to a well and throws a penny straight down the well at 10 m/s. Then she listens for the splash. She hears a splash after 1.5 seconds. How deep is the well?
a) 15 m b) 21 m c) 26 m d) 30 m e) 33 m
17. Aunt Matilda flips a penny straight upward at 5 m/s. It falls down to the floor. It hits the floor
1.3 s after she flips it up. How high was Aunt Matildas hand above the ground when she flipped the coin up?
a) 2.0 m b) 1.8 m c) 1.2 m d) 1.0 m e) 0.7m
18. Cannon shot on level with a muzzle velocity of 30 m/s has a range of 40 m. What was the firing angle?
a) 13o b) 17o c) 21o d) 25o e) 29o
19. A ball is thrown upward. As it passes 10 m height it is traveling at 20 m/s up. What was its initial upward velocity?
a) 24 m/s b) 29 m/s c) 34 m/s d) 39 m/s e) 44 m/s
20. A car goes around a banked
corner (q=10o), m=0.5, at a
velocity of 30 m/s. What is the
minimum radius for the turn if
the car goes around the corner
without sliding?
a) 65 m b) 80 m c) 95 m d) 110 m e) 150 m
Explanation / Answer
https://dl.dropboxusercontent.com/u/79817557/ans.pdf
please check from here and do rate.
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.