Physics homework help.

A bird flies from the south pole to the north pole. Part of the journey is 1000 miles that takes two weeks. What is the birds Ve

alexira [117]

Formula for Velocity = DISTANCE traveled/TIME to travel distance + direction

For this one, we can use mph(miles per hour) as unit.

v = 1,000 miles / 336 hours (2 weeks = 24 hours x 14 days = 336 hrs)
= 2.98 mph North

or we can use kph (kilometers per hour)

v = 1609.34 km / 336 hours (1 mile = 1.60934 km)
= 4.79 kph North

8 0

3 years ago

When you stretch a spring 13 cm past its natural length, it exerts a force of 21

zloy xaker [14]

Answer:

A. 1.6 N/cm

Explanation:

spring constant = 21/13 = 1.6 N/cm

8 0

3 years ago

Assume that the energy lost was entirely due to friction and that the total length of the PVC pipe is 1 meter. Use this length t

gladu [14]

The question is incomplete. The complete question is :

Assume that the energy lost was entirely due to friction and that the total length of the PVC pipe is 1 meter. Use this length to compute the average force of friction (for this calculation, you may neglect uncertainties).

Mass of the ball : 16.3 g

Predicted range : 0.3503 m

Actual range : 1.09 m

Solution :

Given that :

The predicted range is 0.3503 m

Time of the fall is :

$t=\sqrt{\frac{2H}{g}}$

$v_1t= 0.35$ ...........(i)

$v_0t= 1.09$ ...........(ii)

Dividing the equation (ii) by (i)

$\frac{v_0t}{v_1t}=\frac{1.09}{035} = 3.11$

∴ $v_0=3.11 \ v_1$

Now loss of energy = change in the kinetic energy

$W=\frac{1}{2} m [v_0^2-v_1^2]$

$W=\frac{1}{2} \times (16.3 \times 10^{-3}) \times [v_0^2-\left(\frac{v_0}{3.11}\right)^2]$

$W=7.307\times 10^{-3} \ v_0^2$

If f is average friction force, then

(f)(L) = W

(f) (1) = $7.307\times 10^{-3} \ v_0^2$

(f) = $7.307\times 10^{-3} \ v_0^2$

3 0

3 years ago

The amount of energy necessary to remove an electron from an atom is a quantity called the ionization energy, Ei. This energy ca

larisa86 [58]

Answer:

The value is $E_i = 1.5596 *10^{-18} \ J$

Explanation:

From the question we are told that

The wavelength is $\lambda = 48.2 nm = 48.2 *10^{- 9 }\ m$

The velocity is $v = 2.371*10^6 \ m/s$

The mass of electron is $m_e = 9.109*10^{-31} \ kg$

Generally the energy of the incident light is mathematically represented as

$E = \frac{h * c}{\lambda}$

Here c is the speed of light with value $c = 3.0 *10^{8} \ m/s$

h is the Planck constant with value $h = 6.62607015 * 10^{-34 } J\cdot s$

So

$E = \frac{6.62607015 * 10^{-34 }* 3.0 *10^{8}}{48.2 *10^{- 9 }}$

=> $E = 4.12 *10^{-18} \ J$

Generally the kinetic energy is mathematically represented as

$E_k = \frac{1}{2} * m_e * v^2$

=> $E_k = \frac{1}{2} * 9.109*10^{-31} * (2.371*10^6 )^2$

=> $E_k = 2.56 *0^{-18} \ J$

Generally the ionization energy is mathematically represented as

$E_i = 4.12 *10^{-18} - 2.56 *0^{-18}$

=> $E_i = 1.5596 *10^{-18} \ J$

8 0

3 years ago

A syringe containing 1.55 ml of oxygen gas is cooled from 95.3 °c to 0.0 °c. what is the final volume of oxygen gas?\

irinina [24]

Consider the gas to be an ideal gas (it will obey all the introductory gas laws). Also you have to note that the gas will not change phase. It won't.

T_s (Temperature Start) = 95.3o C = 95.3 + 273 = 368.3 oK (degrees Kelvin)
T_e (Temperature End) = 0o C + 273 = 273 oK

Initial volume = Vi = 1.55 mL (no need to change to Liters. The answer will be in mL

Vi /Ts = Ve / Vs Ve is the unknown volume that you seek.
1.55 / 368.3 = Ve / 273
Ve = 1.55 * 273 / 368.3
Ve = 1.1489 mL

If your teacher is concerned about Sig digs, then 0.0 has only two.
Your answer should be 1.1 mL, but I'll give you the choice.

3 0

4 years ago