What happens to the alcohol, as it gets hotter, in the tube of a glass thermometer?

Which object absorbs the most visible light

Papessa [141]

The objects that look black are all tied for first place.

4 0

3 years ago

You are coasting on your 12-kg bicycle at 13 m/s and a 5.0-g bug splatters on your helmet. The bug was initially moving at 1.5 m

Brut [27]

Answer:

a) Pi,c = 1066 kgm/s

b) Pi,b = 0.0075 kgm/s

c) ΔV = - 0.0007 m/s

d) ΔV = - 0.0008 m/s

Explanation:

Given:-

- The mass of the bicycle, mc = 12 kg

- The mass of passenger, mp = 70 kg

- The mass of the bug, mb = 5.0 g

- The initial speed of the bicycle, vpi = 13 m/s

- The initial speed of the bug, vbi = 1.5 m/s

Find:-

a.What is the initial momentum of you plus your bicycle?

b.What is the initial momentum of the bug?

c.What is your change in velocity due to the collision the bug?

d.What would the change in velocity have been if the bug were traveling in the opposite direction?

Solution:-

- First we will set our one dimensional coordinate system, taking right to be positive in the direction of bicycle.

- The initial linear momentum (Pi,c) of the passenger and the bicycle would be:

Pi,c = vpi* ( mc + mp)

Pi,c = 13* ( 12+ 70 )

Pi,c = 1066 kgm/s

- The initial linear momentum (Pi,b) of the bug would be:

Pi,b = vbi*mb

Pi,b = 0.005*1.5

Pi,b = 0.0075 kgm/s

- We will consider the bicycle, the passenger and the bug as a system in isolation on which no external unbalanced forces are acting. This validates the use of linear conservation of momentum.

- The bicycle, passenger and bug all travel in the (+x) direction after the bug splatters on the helmet.

Pi = Pf

Pi,c + Pi,b = V*(mb + mc + mp)

Where, V : The velocity of the (bicycle, passenger and bug) after collision.

1066 + 0.0075 = V*( 0.005 + 12 + 70 )

V = 1066.0075 / 82.005

V = 12.9993 m/s

- The change in velocity is Δv = 13 - 12.9993 = - 0.00070 m/s

- If the bug travels in the opposite direction then the sign of the initial momentum of the bug changes from (+) to (-).

- We will apply the linear conservation of momentum similarly.

Pi = Pf

Pi,c + Pi,b = V*(mb + mc + mp)

1066 - 0.0075 = V*( 0.005 + 12 + 70 )

V = 1065.9925 / 82.005

V = 12.99911 m/s

- The change in velocity is Δv = 13 - 12.99911 = -0.00088 m/s

7 0

4 years ago

Read 2 more answers

Two simple pendulums are in two different places. The length of the second pendulum is 0.4 times the length of the first pendulu

faltersainse [42]

Answer:

$\sqrt{\frac{4}{9}}$

Explanation:

The frequency of a simple pendulum is given by:

$f=\frac{1}{2\pi}\sqrt{\frac{g}{L}}$

where

g is the acceleration of gravity

L is the length of the pendulum

Calling $L_1$ the length of the first pendulum and $g_1$ the acceleration of gravity at the location of the first pendulum, the frequency of the first pendulum is

$f_1=\frac{1}{2\pi}\sqrt{\frac{g_1}{L_1}}$

The length of the second pendulum is 0.4 times the length of the first pendulum, so

$L_2 = 0.4 L_1$

while the acceleration of gravity experienced by the second pendulum is 0.9 times the acceleration of gravity experienced by the first pendulum, so

$g_2 = 0.9 g_1$

So the frequency of the second pendulum is

$f_2=\frac{1}{2\pi}\sqrt{\frac{g_2}{L_2}}=\frac{1}{2\pi} \sqrt{\frac{0.9 g_1}{0.4 L_1}}$

Therefore the ratio between the two frequencies is

$\frac{f_1}{f_2}=\frac{\frac{1}{2\pi}\sqrt{\frac{g_1}{L_1}}}{\frac{1}{2\pi} \sqrt{\frac{0.9 g_1}{0.4 L_1}}}=\sqrt{\frac{0.4}{0.9}}=\sqrt{\frac{4}{9}}$