Seven
The magnitude is pointing towards the origin and is at - 20 degrees. The combination makes 160 with the x axis: C answer
Eight
They keep doing this. They use distance where they should use displacement but they use distance to try and fool you. It's a mighty poor practice.
The distance between the start and end points is the displacement. That "distance" is 180*sqrt(25) = 900 . The actual distance should be 180*4 + 180*3 = 720 + 540 = 1260. That's what a car's odometer or a bicycle odometer would read. the difference is 360.
I really do object to the wording, but what can I do?
Nine
Nine is the same thing as 8.
Displacement = sqrt(400^2 + 80^2)= sqrt(166400) = 408
The actual distance is 400 + 80 = 480
The difference is the answer = 480 - 408 = 72 <<<< Answer
Ten
This is just the displacement magnitude.
dis = sqrt(30^2 + 80^2)
dis = sqrt(900 + 6400)
dis = sqrt(7300)
dis = 85.44 <<<< Answer D
Twelve
Vi = 2.15*Sin(30) = 1.075 m/s
vf = 0
a = - 9.81
t = ?
<u>Formula</u>
a = (vf - vi)/t
<u>Solve</u>
-9.81 = (0 - 1.075)/t
- 9.81 * t = -1.075
t = 0.11 seconds
Thirteen
I'm leaving this last one to you. You need the initial height xo to answer it properly. Judging by the other questions, this one is right.
Edit
That is a surprise! Really quickly
d = 3.2 m
a = - 9.82
vf = 0
vi = ?
vf^2 = vi^2 - 2*a*d
0 = vi^2 - 2*9.81*3.2
vi = sqrt(19.62*3.2)
vi = 8.0 m/s But that is the vertical component of the speed
v = vi/sin(25)
v = 8.0/sin(25) = 11
How do you get out of a room with only a mirror and a table?
Look in the mirror you see what you saw, use the saw to cut the table, half and half makes a hole, jump in it.
Thought you would like that.
Answer:
Alpha decay will produce a daughter nucleus with more protons and beta decay will produce a daughter nucleus with fewer protons than the parent nucleus has.
The correct answer is Destructive Interference.Consider the image attached below. Two waves are travelling towards each other. Blue wave always has a positive peak and the red wave always has a negative peak.
Now imagine these waves are moving through a rope. If blue waves will try to move the rope in positive direction, the red wave will pull it down, and thus the two waves will cancel the effect of each other. Thus resulting in a destructive interference.
Answer:
1) W = 150 J
Explanation:
Work (W) is defined as the product of force F by the distance (d)the body travels due to this force.
W= F*d Formula ( 1)
The work is positive (W+) if the force has the same direction of movement of the object.
The work is negative (W-) if the force has the opposite direction of the movement of the object.
The component of the force that performs work must be parallel to the displacement.
Work done to lift the floor box to its final position
We apply the formula (1)
W= F*d
W = (100 N)*(1.5 m)
W = 150 J