All categories

3 years ago

Help please! This question is driving me crazy

Physics

1 answer:

Varvara68 [4.7K]3 years ago

3 0

Answer:

-10.8°, or 10.8° below the +x axis

Explanation:

The x component of the resultant vector is:

x = 3.14 cos(30.0°) + 2.71 cos(-60.0°)

x = 4.07

The y component of the resultant vector is:

y = 3.14 sin(30.0°) + 2.71 sin(-60.0°)

y = -0.777

Therefore, the angle between the resultant vector and the +x axis is:

θ = atan(y / x)

θ = atan(-0.777 / 4.07)

θ = -10.8°

The angle is -10.8°, or 10.8° below the +x axis.

You might be interested in

If a wave has amplitude of 2 meters, a wavelength of 5 meters, and a frequency of 60 Hz, at what speed is it moving?

klemol [59]

The relationship between speed of a wave w, frequency f and wavelength $\lambda$ is
$v = \lambda f$
For the wave of our problem, $\lambda = 5 m$ and f=60 Hz, so its speed is
$v=(5 m)(60 Hz)=300 m/s$

5 0

3 years ago

Read 2 more answers

Calculate the self-inductance (in mH) of a 45.0 cm long, 10.0 cm diameter solenoid having 1000 loops. mH (b) How much energy (in

Karo-lina-s [1.5K]

Answer:

(a) The self inductance, L = 21.95 mH

(b) The energy stored, E = 4.84 J

Explanation:

(a) Self inductance is calculated as;

$L = \frac{N^2 \mu_0 A}{l}$

where;

N is the number of turns = 1000 loops

μ is the permeability of free space = 4π x 10⁻⁷ H/m

l is the length of the inductor, = 45 cm = 0.45 m

A is the area of the inductor (given diameter = 10 cm = 0.1 m)

$A = \pi r^2 = \frac{\pi d^2}{4} = \frac{\pi \times (0.1)^2}{4} = 0.00786 \ m^2$

$L = \frac{(1000)^2 \times (4\pi \times 10^{-7}) \times (0.00786)}{0.45} \\\\L = 0.02195 \ H\\\\L = 21.95 \ mH$

(b) The energy stored in the inductor when 21 A current ;

$E = \frac{1}{2}LI^2\\\\E = \frac{1}{2} \times (0.02195) \times (21) ^2\\\\E = 4.84 \ J$

$emf = L \frac{\Delta I}{\Delta t} \\\\t = \frac{LI}{emf} \\\\t = \frac{0.02195 \times 21}{3} \\\\t = 0.154 \ s$

3 0

3 years ago

How long must a 400w electrical engine work in order to produce 300kj of work

vladimir1956 [14]

Answer:

300000 J / 400 J/s = 750 s = 12.5 minutes

Explanation:

8 0

2 years ago

State how you agree or disagree with the following statement. A good circuit cannot have internal resistance.

Rashid [163]

Answer: I do

Explanation:

Resistance opposes current thereby reducing the amount of current that flows through a circuit. In other words, it leads to a loss of electrical energy.

Ideally speaking, a good circuit should have no internal resistance as this would lead to more energy having to be supplied to overcome that resistance. External resistance however, is not a bad thing. For instance, oxygen being removed from lightbulbs.

7 0

3 years ago

Water, H2O ,and methane ,CH4, are both covalent substances . why is water a liquid at room temperature while methane is a gas ?

stiv31 [10]

I think the answer is b

7 0

3 years ago

Read 2 more answers