1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
ira [324]
3 years ago
15

Two vectors are presented as a=3.0i +5.0j and b=2.0i+4.0j find (a) a x b, ab (c) (a+b)b and (d) the component of a along the dir

ection of
b.
Physics
1 answer:
Svet_ta [14]3 years ago
3 0
Let's ask this question step by step:
 Part A) 
 a x b = (3.0i + 5.0j) x (2.0i + 4.0j) = (12-10) k = 2k
 ab = (3.0i + 5.0j). (2.0i + 4.0j) = 6 + 20 = 26
 Part (c)
 (a + b) b = [(3.0i + 5.0j) + (2.0i + 4.0j)]. (2.0i + 4.0j)
 (a + b) b = (5.0i + 9.0j). (2.0i + 4.0j)
 (a + b) b = 10 + 36
 (a + b) b = 46
 Part (d)
 comp (ba) = (a.b) / lbl
 a.b = (3.0i + 5.0j). (2.0i + 4.0j) = 6 + 20 = 26
 lbl = root ((2.0) ^ 2 + (4.0) ^ 2) = root (20)
 comp (ba) = 26 / root (20)
 answer
 2k
 26
 46
 26 / root (20)
You might be interested in
Which of these is exhibiting kinetic energy?1) a rock on a mountain ledge2) a space station orbiting Earth 3) a person sitting o
jarptica [38.1K]

The answer would be:

A space station orbiting Earth.

7 0
3 years ago
Read 2 more answers
When the play button is pressed, a CD accelerates uniformly from rest to 450 rev/min in 3.0 revolutions. If the CD has a radius
Marina CMI [18]

To solve this problem it is necessary to apply the kinematic equations of angular motion.

Torque from the rotational movement is defined as

\tau = I\alpha

where

I = Moment of inertia \rightarrow \frac{1}{2}mr^2 For a disk

\alpha = Angular acceleration

The angular acceleration at the same time can be defined as function of angular velocity and angular displacement (Without considering time) through the expression:

2 \alpha \theta = \omega_f^2-\omega_i^2

Where

\omega_{f,i} = Final and Initial Angular velocity

\alpha = Angular acceleration

\theta = Angular displacement

Our values are given as

\omega_i = 0 rad/s

\omega_f = 450rev/min (\frac{1min}{60s})(\frac{2\pi rad}{1rev})

\omega_f = 47.12rad/s

\theta = 3 rev (\frac{2\pi rad}{1rev}) \rightarrow 6\pi rad

r = 7cm = 7*10^{-2}m

m = 17g = 17*10^{-3}kg

Using the expression of angular acceleration we can find the to then find the torque, that is,

2\alpha\theta=\omega_f^2-\omega_i^2

\alpha=\frac{\omega_f^2-\omega_i^2}{2\theta}

\alpha = \frac{47.12^2-0^2}{2*6\pi}

\alpha = 58.89rad/s^2

With the expression of the acceleration found it is now necessary to replace it on the torque equation and the respective moment of inertia for the disk, so

\tau = I\alpha

\tau = (\frac{1}{2}mr^2)\alpha

\tau = (\frac{1}{2}(17*10^{-3})(7*10^{-2})^2)(58.89)

\tau = 0.00245N\cdot m \approx 2.45*10^{-3}N\cdot m

Therefore the torque exerted on it is 2.45*10^{-3}N\cdot m

3 0
3 years ago
An electric motor consumes 9.00 kj of electrical energy in 1.00 min. if one-third of this energy goes into heat and other forms
liq [111]
How do I make a question help PLZZZ
5 0
3 years ago
Suppose I have a vector that is 7 units long and that makes an angle of +30 degrees from the positive x-axis. I want to add to t
Vinil7 [7]

Answer:

sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j

Explanation:

We have given first vector which has length of 7 units and makes an angle of 30° with positive x-axis

So x component of the vector =7cos30^{\circ}=7\times 0.866=6.06

y component of the vector =7sin30^{\circ}=7\times 0.5=3.5

So vector will be 6.06i+3.5j

Now other vector of length of 7 units and makes an angle of 120° with positive x-axis

So x component of vector  =7cos120^{\circ}=7\times -0.5=-3.5i

y component of the vector =7sin120^{\circ}=7\times 0.866=6.06j

Now sum of these two vectors is 6.06i+3.5j-3.5i+6.06j = 2.56i+9.56j

5 0
3 years ago
Which waves require a material medium for transmission? a.) light waves b.) radio waves c.) sound waves d.) microwaves
shepuryov [24]

Answer:

mechanical waves require a medium

5 0
3 years ago
Other questions:
  • Calculate the average force that must be exerted on a 0.145 kg baseball in order to give it an acceleration of 130 m/s^2. (round
    6·2 answers
  • . Consider a fully extended arm that is rotating about the shoulder such that with a shoulder-to-hand length of 30 cm. If the ar
    12·1 answer
  • In which scenario will the two objects have the greatest gravitational force
    13·2 answers
  • Which of the following is an example of a primary source?
    15·1 answer
  • One advantage of the __________ model is quick recognition. A. prototype B. exemplar C. language D. concept Please select the be
    9·1 answer
  • What is another name for Kepler's first law? A. law of periods B. law of ellipses C. law of universal gravitation D. law of equa
    15·1 answer
  • STATION 1
    13·1 answer
  • 1 Write 7 next to the statements that are true.
    5·1 answer
  • What are two serious condition of the circulatory system?
    5·2 answers
  • You are standing on a moving bus, facing forward, and you suddenly fall forward. You can imply form this that the bus’s a. Veloc
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!