Chapter 4 and 3 physics
A submarine dives from the water surface at an angle of 30° below the horizontal, following a straight path 50 m long. How far is the submarine then below the water surface?
(50 m) sin 30°
As a projectile thrown upward moves in its parabolic path, at what point along its path are the velocity and acceleration vectors for the projectile perpendicular to each other?
(a)the highest point
An astronaut hits a golf ball on the Moon. Which of the following quantities, if any, remain constant as a ball travels through the vacuum there? (Select all that apply.)
(b) horizontal component of velocity e) acceleration.
For the resultant of two vectors to be maximum, the angle between them should be
0
what is the y component of the vector (3i-8k)m/s
0. because it goes (i,j,k)(x,y,z)
What is the magnitude of the vector (12i-5j) m/s? Here iand jare unit vectors.
13 fom (12^2+5^2) the sqrt
what is the magnitude of vector 10i-10k m/s
14.4. take squared over square root
If vector B is added to vector A , which two of the following choices must be true for the resultant vector to be equal to zero?
A and B are parallel and in opposite directions. A and B have the same magnitude.
For which of the following vectors is the magnitude of the vector equal to one of the components of the vector?
C=5K
A set of keys on the end of a string is swung steadily in a horizontal circle. In one trial, it moves at speed v in a circle of radius r. In a second trial, it moves at a higher speed 4v in a circle of radius 4r. In the second trial, how does the period of its motion compare with its period in the first trial?
It is the same as in the first trial.
If you know the position vectors of a particle at two points along its path and also know the time it took to get from one point to the other, can you determine the particle's instantaneous velocity and average velocity? (Select all that apply.)
The average velocity can be determined
A component of a vector is ______________ less or equal than the magnitude of the vector.
always
A car moving around a circular track with constant speed has
an acceleration directed toward the center of its path.
If the magnitude of sum of the two vector is equal to the magnitude of the difference between them, then the angle between the vectors is
be perpendicular
The cutting tool on a lathe is given two displacements, one of magnitude 4 cm and one of magnitude 3 cm, in each one of five situations (a) through (e) diagrammed in Figure below. Rank these situations according to the magnitude of the total displacement of the tool, putting the situation with the greatest resultant magnitude first. If the total displacement is the same size in two situations, give those letters equal ranks.
c = e > a > d > b
What are examples of vectors
displacement, velocity,acceleration,force,temperature change
What are examples of Scalars
distance, speed, time, temp
In this situation is the moving object appropriately modeled as a projectile? A diver throws a stone under water.
no
In this situation is the moving object appropriately modeled as a projectile? A jet airplane crosses the sky with its engines thrusting the plane forward.
no jet exerts extra force
velocity and acceleration are never?
parallel
Vector A lies in the xy plane. Both of its components will be negative if it lies in which quadrant(s)?
the third quadrant
Which of the following are scalar quantities?
your age, speed, mass
