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
Nonamiya [84]
3 years ago
11

Alex, parked by the side of an east-west road, is watching car P, which is moving in a westerly direction. Barbara, driving east

at a speed 52 km/h, watches the same car. Take the easterly direction as positive. If Alex measures a speed of 78 km/h for car P, what velocity will Barbara measure?
Physics
1 answer:
Alexxandr [17]3 years ago
6 0

Answer:

v_{PB} = 130\ km/h

Explanation:

Since, Alex is at rest. Therefore, the speed measured by him will be the absolute speed of car P. Therefore, taking easterly direction as positive:

Absolute\ Velocity\ of\ Car\ P = v_{P} = -78\ km/h

And the absolute velocity of Barbara's Car is given as:Absolute\ Velocity\ of\ Barbara's\ Car = v_{B} = 52\ km/h

Now, for the velocity of Car p with respect to the velocity of Barbara's Car can be given s follows:

Velocity\ of\ Car\ P\ measured\ by\ Barbara = v_{PB} = v_{B}-v_{P}\\\\v_{PB} = 52\ km/h-(-78\ km/h)

v_{PB} = 130\ km/h

You might be interested in
A hybrid is
Sophie [7]
The correct answer is heterozygous.
7 0
4 years ago
Read 2 more answers
1. A ball of mass 3kg is placed in a catapult which is pulled back by
irakobra [83]

Explanation:

jjckg xoz 96 dzod I o6d 69f 07r 80ct

5 0
3 years ago
Particle A of charge 2.70 10-4 C is at the origin, particle B of charge -6.36 10-4 C is at (4.00 m, 0), and particle C of charge
Serhud [2]

Answer:

FC vector representation

F_{C} =(19.03i+13.78j)N

Magnitude of FC

F_{C}=23.495N

Vector direction FC

\beta=35.91 degrees: angle that forms FC with the horizontal

Explanation:

Conceptual analysis

Because the particle C is close to two other electrically charged particles, it will experience two electrical forces and the solution of the problem is of a vector nature.

The directions of the individual forces exerted by qA and qB on qC are shown in the attached figure; The force (FAC) of qA over qC is repulsive because they have equal signs and the force (FBC) of qB over qC is attractive because they have opposite signs.

The FAC force is up in the positive direction and the FBC force forms an α angle with respect to the x axis.

\alpha = tan^{-1}(\frac{3}{4}) = 36.86 degrees

To calculate the magnitudes of the forces we apply Coulomb's law:

F_{AC} = \frac{k*q_{A}*q_{C}}{r_{AC}^2} Equation (1): Magnitude of the electric force of the charge qA over the charge qC

F_{BC} = \frac{k*q_{B}*q_{C}}{r_{BC}^2} Equation (2) : Magnitude of the electric force of the charge qB over the charge qC

Known data

k=8.99*10^9 \frac{N*m^2}{C^2}

q_{A}=2.70*10^{-4} C

q_{B}=-6.36*10^{-4} C

q_{C}=1.04*10^{-4} C

r_{AC} =3

r_{BC}=\sqrt{4^2+3^2} = 5

Problem development

In the equations (1) and (2) to calculate FAC Y FBC:

F_{AC} =8.99*10^9*(2.70*10^{-4}* 1.04*10^{-4})/(3)^2=28.05N

F_{BC} =8.99*10^9*(6.36*10^{-4}* 1.04*10^{-4})/(5)^2=23.785N

Components of the FBC force at x and y:

F_{BCx}=23.785 *Cos(36.86)=19.03N

F_{BCy}=23.785 *Sin(36.86)=14.27N

Components of the resulting force acting on qC:

F_{Cx} = F_{ACx}+ F_{BCx}=0+19.03=19.03N

F_{Cy} = F_{ACy}+ F_{BCy}=28.05-14.27=13.78N

FC vector representation

F_{C} =(19.03i+13.78j)N

Magnitude of FC

F_{C}= \sqrt{19.03^2+13.78^2} =23.495N

Vector direction FC

\beta = tan^{-1} (\frac{13.78}{19.03})=35.91 degrees: angle that forms FC with the horizontal

7 0
3 years ago
Calculate the magnitude of the following vector components in OX and OY directions​
12345 [234]

Answer:

Very easy question

For x-component, we use Fₓ = Fcosα

For y-component, we use Fy = Fsinα

The major problem is with angle α.

Here α = 90+30

Because the angle is measured from +ve X-axis.

By putting values if you know co-ratios that how Sin and cos Convert to each other then you have got it.

So for further calculation,

Fₓ = Fcos(90+30) = 25(-sin30)

Fₓ = -25(1/2) = 25/2 = 12.5  - will be eliminate because force in magnitude is not "-ve"

As it is

Fy = Fsin(90+30) = Fcos30

Fy = 25 (√3 /2) = 25√3/2

......................................................................................

3 0
3 years ago
10.What is the Kinetic Energy of a 150 kg object that is moving with a speed<br> of 15 m/s? (7b)
madam [21]
KE=1/2 mv^2
=1/2(150kg)(15m/s)^2
=16875 kgms^-2
4 0
4 years ago
Other questions:
  • Suppose you are measuring double‑slit interference patterns using an optics kit that contains the following options that you can
    14·1 answer
  • Thermopane window is constructed, using two layers of glass 4.0 mm thick, separated by an air space of 5.0 mm.
    15·1 answer
  • An experiment is set up to test the angular resolution of an optical device when red light (wavelength ????r ) shines on an aper
    5·1 answer
  • The difference between speed and velocity is that velocity includes.
    7·2 answers
  • A photon with a frequency of 5.48 × 1014 hertz is emitted when an electron in a mercury atom falls to a lower energy level. Iden
    14·1 answer
  • A compass originally points North; at this location the horizontal component of the Earth's magnetic field has a magnitude of 2e
    12·1 answer
  • Give two examples of vernier calliper
    8·1 answer
  • What is the direction of a vector with an x component of -12 m and a y component of -15 m?
    10·1 answer
  • A car starts from rest and after 20 seconds it's velocity becomes 108km find the acceleration of the car
    15·1 answer
  • Hecto the Mornar a fursa explain i magnituse of the force acting right angle to the moment arm​
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!