1. b right
2. AhhhgggHHH a is 1 g downward the whole time whatever is airborne
3. b right
4. sqrt(10^2+10^2) =10sqrt2 = 14 c
5. c! when you reach steep enough it goes to zero
6. B ! the forces are ALWAYS equal and opposite (Law 3) however unless the friction on the ground or in wheels is included, the cart accelerates.
7. b yes
Sorry if it is alot of questions
1. A crate falls from an airplane flying horizontally at an altitude of 2000 m. Neglecting air resistance, about
how long will the crate take to strike the ground?
a. 10 seconds
b. 20 seconds
c. 400 seconds
d. 100 seconds
2. An object is dropped and falls freely to the ground with an acceleration of 1 g. If it is thrown upward at an
angle instead, its acceleration would be __________.
a. 0 g.
b. 1 g downward.
c. 1 g upward.
d. larger than 1 g.
e. none of the above
3. A projectile is thrown upward and moves in a parabolic path. At what point along this path are the velocity
and acceleration vectors for the projectile perpendicular to each other?
a. Nowhere
b. At the highest point
c. At the launch point
d. Unable to determine
4. Which best approximates the resultant of a pair of 10-unit vectors at right angles to each other?
a. 0 N.
b. 10 N.
c. 14 N.
d. 20 N.
5. When the angle of an incline with a block resting on it increases, the normal support force __________.
a. increases.
b. stays the same.
c. decreases.
6. If a horse pulls on a wagon at rest, the wagon pulls back equally as much on the horse. Will the wagon be set
into motion?
a. No, because the forces cancel each other.
b. Yes, because there is a net force acting on the wagon.
c. Yes, because there is a time delay between action and reaction.
d. Yes - The horse's pull on the wagon is larger than the wagon's pull on the horse.
7. An object following a straight-line path at constant speed __________.
a. has a net force acting on it in the direction of motion.
b. has zero acceleration.
c. must be moving in a vacuum.
d. has no forces acting on it.
e. none of the above
Answers:
1.b
2.c
3.b
4.b
5.b
6.a
7.b
2 answers
Thank You Sir
2 answers