問題一覧
1
Which of the following is not a fundamental physical quantity?
velocity
2
A quantity having both magnitude and direction is called a vector quantity. Which below can be represented by a vector quantity?
displacement
3
Two forces, one 40 Newton, the other 26 Newton act on a body. The directions of the forces are unknown. What is the minimum possible magnitude of the resultant vector
14 N
4
In the previous problem, what is the maximum possible magnitude of the resultant vector?
14 N
5
What is the resultant of this system?
100 N located on the 4th quadrant
6
After reaching the finish line 100 m. from the starting line, runner A moves 5 m. beyond the finish line and then goes back to meet runner B. When they meet, runner B is still 10 m. away from the finish line. What is the net displacement of runner A?
90 m. to the right of the starting line
7
A can of biscuit is usually opened with a spoon. When used this way the spoon is an example of a lever. Which statement best describes the positions of the effort, fulcrum and resistance?
The fulcrum is between the resistance and effort.
8
The efficiency of a machine is:
always less than 100%
9
When an object moves at constant velocity, the net force acting on it is
zero
10
The tendency of a body to remain at rest or in motion unless acted upon by an external unbalanced force:
inertia
11
When an object falls freely, its acceleration is:
constant
12
Calculate the rate of acceleration for a runner who reaches a speed of 2 m/s in 10 seconds. a. C. d.
0.2 m/s^2
13
For a ball thrown vertically upward, the time it takes to reach its maximum height is_the time it takes to go down.
equal to
14
When a stone is thrown up into the air, at what point in its flight is the velocity decreasing?
before it reaches the highest point
15
What can you say about the motion of a stone thrown vertically upwards? a. b. C. d.
The stone increases speed as it falls from maximum height at constant acceleration.
16
When will the ball reach a speed of 49 m/s?
after 5s and 15 s
17
What is the maximum height that the ball will reach?
490 m
18
Which of the following is true?
The potential energy for I is greater than the kinetic energy for ll.
19
Which of the following is not true about a projectile fired at 196 m/s at an angle of 30 degrees with the horizontal? All of the
It has zero acceleration when it reaches maximum height.
20
Which of the following is not true about a projectile fired at 196 m/s at an angle of 30 degrees with the horizontal?
Velocity decreases to zero when it reaches maximum height then increases further on.
21
According to the Law of Conservation of Momentum, the total momentum of a system before a collision is the total momentum of the system after collision.
equal to
22
A bullet of mass 0.01 kg is fired into suspended wooden block of mass 0.29 kg at 120 meters/second. If the bullet remains in the block after the collision, what is the final velocity of the bullet and block?
4 m/s
23
Which of the following is not a unit of pressure?
Joule
24
A lift of mass 1700 kg moves upwards with an acceleration of 1.5 m/s?. What is the upward force acting on the lift?
2550 N
25
In the previous problem, what is the weight of the lift?
16660 N
26
A 10 kg mass is held 1.0 m above a table for 25 seconds. How much work is done during that period?
0 Joules
27
A horse exerts a force of 3,000 N while pulling a cart for 6 km. How much work does the horse do? Give your answer in mega joules
18 MJ
28
A rocket coasting along in space at some speed, V, fires Its engines thus doubling its speed. At the same time, It unloads some cargo reducing its mass to half Its value. In the process, Its kinetic energy is a,
doubled
29
In an activity, Joel observed that there are two sets of circular waves spreading out across the surface of the water in the tank. This shows:
diffraction
30
The term used to describe the constant random motion of colloidal particles.
Brownian movement
31
When a long, straight wooden pole is partly submerged in water, the pole looks bent. What explains this phenomenon?
refraction
32
Which is true of sound waves?
both a and b
33
A race car emits a distinctive roar when it passes you and slowly the frequency decreases as it moves away, it exhibits:
Doppler effect
34
Which scientist would have most likely used phrases "equal areas", "planetary period", and "elliptic foci”?
Johannes Kepler
35
To calculate the gravitational force between two objects, you do net need to know the:
acceleration of both objects
36
The force of attraction between 2 identical bodies of 1 kg mass and separated distance of 1 meter.
6.67 x 10^-11 newtons
37
The statements below comprises Keplers' Laws of Planetary Motion except for:
The periods of the planet are proportional to 3/2 powers of the major axis lengths of their orbits
38
The first law of thermodynamics states that:
While the kind of energy in a closed system can change, the total amount cannot.
39
A boy spins vertically a marble attached to a string. At which point is the tension greatest?
at the lowest point
40
What has to happen for an object to maintain a circular path?
the speed must be kept constant
41
Uniform circular motion involves:
change in direction but not change in speed