ASAP pls

. On a safari, a team of naturalists sets out toward a research station located 9.6 km away in a direction 42° north of east. Af

Elden [556K]

Answer: $\theta =49.76^{\circ}$ North of east

Explanation:

Given

Research station is 9.6 km away in $42^{\circ}$ North of east

after travelling 3.1 km $25^{\circ}$ north of east

Position vector of safari after 3.1 km is

$r_2=3.1cos25\hat{i}+3.1sin25\hat{j}$

Position vector if had traveled correctly is

$r_0=9.6cos42\hat{i}+9.6sin42\hat{j}$

Now applying triangle law of vector addition we can get the required vector $(r_1)$

$r_1+r_2=r_0$

$r_1=(9.6cos42-3.1cos25)\hat{i}+(9.6sin42-3.1sin25)\hat{j}$

$r_1=4.325\hat{i}+5.112\hat{j}$

Direction is given by

$tan\theta =\frac{y}{x}=\frac{5.112}{4.325}$

$\theta =49.76^{\circ}$

8 0

3 years ago

Suppose you toss a tennis ball upward.a) Does the kinetic energy of the ball increase or decrease as it moves higher?b) What hap

Lilit [14]

Answer:

a) No. The kinetic energy of the ball decreases.

b) The potential energy of the ball increases.

c) The ball would go half of the original distance.

Explanation:

a) The kinetic energy would be converted to potential energy as the ball goes higher. Since the total mechanical energy is conserved, the kinetic energy would decrease.

b) The potential energy of the ball would increase. Since the total mechanical energy of the ball is conserved, the ball would lose speed, and therefore kinetic energy. In order to compensate the loss of kinetic energy, the ball would gain potential energy as it goes higher.

c) The relation of the energy and mass is as follows:

$K = \frac{1}{2}mv^2\\U = mgh$

According to the energy conservation

$K_1 + U_1 = K_2 + U_2\\\frac{1}{2}mv^2 + 0 = 0 + mgh\\\frac{1}{2}v^2 = gh$

The maximum height that the ball reaches is proportional to the initial velocity. If the ball would be imparted with the same amount of energy, its final potential energy would be the same. However, in order to have the same potential energy (mgh), its height would be half of the original case.

$mgh = (2m)g(\frac{h}{2})$

7 0

3 years ago

You have 2 resistors of unknown values you label Ra and Rb. You have an old battery and a multimeter you bought years ago for 7$

Veseljchak [2.6K]

Answer:

the answers, the correct one is D, Rb₂ = 29.97 ohm

Explanation:

For this exercise we use ohm's law and the equivalent resistance ratio for series and parallel circuits.

Serial circuit

(Ra + Rb) is = V

(Ra + Rb) 0.111 = 10

(Ra + Rb) = 10 / 0.111 = 90.09

parallel circuit

$\frac{1}{R} = \frac{1}{Ra} + \frac{1}{Rb}$

R = $\frac{Ra \ Rb}{Ra + Rb}$

\frac{Ra \ Rb}{Ra + Rb} i_p = V

\frac{Ra \ Rb}{Ra + Rb} 0.5 = 10

\frac{Ra \ Rb}{Ra + Rb} = 10 / 0.5 = 20

we write and solve our system of equations

Ra + Rb = 90.09

\frac{Ra \ Rb}{Ra + Rb} = 20

we solve for Ra in the first equation

Ra = 90.09 - Rb

RaRb = 20 (Ra + Rb)

we substitute Ra in the second equation

(90.09-Rb) Rb = 20 [(90.09-Rb) + Rb]

90.09 Rb - Rb² = 20 90.09

Rb² - 90.09 Rb + 1801.8 = 0

we solve the quadratic equation

Rb = [90.09 ± $\sqrt{90.09^2 - 4 \ 1801.8}$ ] / 2

Rb = [90.09 ± 30.15] / 2

Rb₁ = 60.12 ohm

Rb₂ = 29.97 ohm

the smallest value is Rb = 30 ohm

When checking the answers, the correct one is D

6 0

3 years ago

Which statement supports the idea that the Earth rotates on its axis?

Ivenika [448]

Answer:

c

Explanation:

because the other would not make sense

3 0

3 years ago

What happened during the Big Bang

Fynjy0 [20]

Answer:

The universe began, scientists believe, with every speck of its energy jammed into a very tiny point. This extremely dense point exploded with unimaginable force, creating matter and propelling it outward to make the billions of galaxies of our vast universe. Astrophysicists dubbed this titanic explosion the Big Bang.

3 0

3 years ago