Question 14

You walk 53 m to the north, then you turn 60° to your right and walk another 45 m. Determine the direction of your displacement

Anton [14]

Answer:

NE 60*

Explanation:

4 0

3 years ago

A 75 kg football player is gliding forward across very smooth ice at 4.6 m/s. He throws a 0.47 kg football straight forward. A)

lord [1]

Answer:

4.53482 m/s

4.506 m/s

Explanation:

$m_1$ = Mass of player = 75 kg

$v_1$ = Initial velocity of player = 4.6 m/s

$m_2$ = Mass of ball = 0.47 kg

$v_1$ = Initial velocity of ball = 15 m/s

The linear momentum of the system is conserved

$(m_1+m_2)v_1=m_1v+m_2v_2\\\Rightarrow v=\dfrac{(m_1+m_2)v_1-m_2v_2}{m_1}\\\Rightarrow v=\dfrac{(75+0.47)4.6-0.47\times 15}{75}\\\Rightarrow v=4.53482\ m/s$

The player's speed is 4.53482 m/s

In the second case the equation of momentum is

$(m_1+m_2)v_1=m_1v+m_2(v_2+v_1)\\\Rightarrow v=\dfrac{(m_1+m_2)v_1-m_2(v_2+v_1)}{m_1}\\\Rightarrow v=\dfrac{(75+0.47)4.6-0.47\times (15+4.6)}{75}\\\Rightarrow v=4.506\ m/s$

The player's speed is 4.506 m/s

4 0

4 years ago

While riding on I-26 towards Columbia, your mother slams on the brakes, to avoid hitting the car in front of her. Both of your b

emmasim [6.3K]

Hi,

Newton's Law of Inertia explains this action because the resistance of the seat belt allows the change in its state of motion. So because the change of speed, your body moves forward but is restricted by the seat belt.

Have a great day!

4 0

3 years ago

A bob of mass m = 0.250 kg is suspended from a fixed point with a massless string of length L = 22.0 cm. You will investigate th

katen-ka-za [31]

To solve the problem, it is necessary to use the concepts of gravitational force, centripetal force and trigonometric components that can be extrapolated from the statement.

By definition we know that the Force of Gravity is given by

$F_g=mg$

Where,

m= Mass

g = Gravitational Acceleration

The centripetal force is given by,

$F_c = \frac{mv^2}{R}$

Where,

m = Mass

v = Velocity

R = Radius

For the case described in the problem, the Force of gravity the net component would be given by sin?, While for the centripetal force the net component is in the horizontal direction, therefore it corresponds to the $cos\theta$

Then,

$F_g = mg sin\theta$

$F_c = \frac{mv^2}{r}cos\theta$

From the radius we have its length but not the net height, which would be given by

$r = L sin\theta$

So equating the equations we have to

$F_g = F_c$

$mg sin\theta=\frac{mv^2}{r}cos\theta$

$mg sin\theta=\frac{mv^2}{Lsin\theta}cos\theta$

Re-arrange to find v,

$v = \sqrt{\frac{gLsin^2\theta}{cos\theta}}$

Replacing with our values

$v = \sqrt{\frac{(9.8)(22*10^{-2})(sin^2 24)}{cos24}}$

$v = 0.624$

Therefore the tangential velocity of the mass is 0.624m/s

5 0

4 years ago

Scenario: You place a mug of hot tea on the table in a cool room.

Shkiper50 [21]

A. Radiation, conduction

B.
*Radiation will occur between the mug of hot tea and the room
*conduction will occur between the mug of hot tea and the table

C. The table as well as the surrounding air will become warmer.
This is because heat is given off from the mug of hot tea.

6 0

3 years ago