SAT试题
1.An object that’s moving with constant speed travels once around a circular path.True statements about this motion include which of the following?
A.The displacement is zero B. The average speed is zero
C. The acceleration is zero D. None of the above
A
2.Which of the following must always be true?
1.If an object’s acceleration is constant,then it must move in a straight line
2.If an object’s acceleration is zero,then its speed must remain constant
3.If an object’s speed remains constant,then its acceleration must be zero.
A.1 and 2 only B.1 and 3 only C.2 only D.3 only E.2 and 3 only
C
本科学历办理4.A frictionless inclined plane of length 20m has a maximum vertical height of 5m. If an object of mass 2 kg is planced on the plame . Which of the following best approximates the net force it feels?
elitesA.5N B.10N C.15N D.20N E.30N
A
5.A person who weighs 800N steps onto a scale that is on the floor of an elevator car. If the elevator accelerates upward at a rate of 5 m/s, what will the scale read?
A.400N B.800N C.1000N D.1200N E.1600N
D
6.A person standing on a horizontal floor feels two forces: the downward pull of gravity and the upward supporting force from the floor. There two forces
A. have equal magnitudes and from an action /reaction pair
B. have equal magnitudes but do not from an action /reaction pair
C. have unequal magnitudes and from an action /reaction pair
D. have unequal magnitudes and do not from an action /reaction pair
E.None of the above
B
7.How long would it take a car,starting from rest and accelerating uniformly in a straight line at 5m/s,to cover a distance of 200m?
genreA.9s B 10.5s C.12.0s D.15.5s E.20.0s
A
8.A rock is dropped off a cliff and strikes the ground with an impact velocity of 30m/s.How
high was the cliff?
A.15m B.20m C.30m D.45m E.60m
D
9.A soccer ball at rest on the ground,is kicked with an initial velocity of 10m/s at a launch angle of 30.Calculate its total flight time , assuming that air resistance is negligible.
A.0.5s B.1s C.1.7s D.2s E.4s
B
10.If all of the forces acting on an object balance so that the net force is zero , then
A.the object must be at rest
B. the object’s speed will decrea
C. the object will follow a parbolic trajectoryamg是什么意思
D. the object’s direction of motion can change,but its speed cannot
E.None of the above
E
11.The coefficient of static friction between a box and a ramp is 0.5. The ramp’s incline angle is 30.If the box is placed at rest on the ramp, box will
A. accelerate down the ramp
B. accelerate briefly down the ramp but then slow down and stop
C.move with constant velocity down the ramp
567go
D.not move
E.Cannot be determined from the information given
gemstones of the worldA
do you love me翻译12.A 20N block is being pushed across a horizontal table by an 18N force . If the coefficient of kinetic friction between the block and the table is 0.4. find he acceleration of the block
A.0.5 m/s B.1 m/s C.5 m/s D.7.5 m/s E.9m/s
C
13.A stone is thrown horizontally with an initial speed of 30m/s from a bridge.Find the stone’s total speed when it enters the water 4 conds later(Ignore air resistance.)
A.30m/s B.40m/s C.50m/s D.60m/s E.70m/s
C
课14.Which one of the following statements is true concerning the motion of an ideal projectile launched at an angle of 45 to the borizontal?
A.The acceleration vector points opposite to the velocity vector on the way up and in the
same direction as the velocity vector on the way downsurvive
B.The speed at the top of the trajectory is zero.
C.The object’s total speed remains constant during the entire flight
D.The horizontal speed decreas on the way up and increas on the way down
E.The vertical speed decreas on the way up and increas on the way down
E
15.Which pair of forces can produce a resultant of 15 newtons?
A.20N,20N B.25N,5N C.5N,5N D.7N,7N E.5N,3N
A
16.Two crates are stacked on top of each other on a horizontal floor , crate #1 is on the bottom , and crate #2 is on the top . Both crates have the same mass . Compared with the strength of the force Fnecessary to push only crate #1 at a constant speed across the floor, the strength of the force F英语介绍自己necessary to push the stack at the same constant speed across the floor is greater than Fbecau
A.the force of the floor on crate #1 is greater
