Sonny took 16 seconds to finish a 100-m race. What was<br> Sonny's average speed in the race

A 10 kg ball strikes a wall with a velocity of 3 m/s to the left. The ball bounces off with a velocity of 3 m/s to the right. If

lord [1]

Answer:

The force is 272.73 newtons

Explanation:

We're going to use impulse-momentum theorem that states impulse is the change on the linear momentum this is:

$\overrightarrow{J}=\overrightarrow{p}_{f}-\overrightarrow{p}_{i}$ (1)

Impulse is also defined as average force times the time the force is applied:

$\overrightarrow{J}=\overrightarrow{F}_{avg}(\varDelta t)$ (2)

By (2) on (1):

$\overrightarrow{F}_{avg}(\varDelta t)= \overrightarrow{p}_{f}-\overrightarrow{p}_{i}$

solving for $\overrightarrow{F}_{avg}$ :

$\overrightarrow{F}_{avg}=\frac{\overrightarrow{p}_{f}-\overrightarrow{p}_{i}}{\varDelta t}$ (3)

We already know Δt is equal to 0.22 s, all we should do now is to find $\overrightarrow{p}_{f}-\overrightarrow{p}_{i}$ and put on (3) ( $\overrightarrow{p_{i}}$ the initial momentum and $\overrightarrow{p_{f}}$ the final momentum). Linear momentum is defined as $\overrightarrow{p}=m\overrightarrow{v}$ , using that on (3):

$\varDelta\overrightarrow{p}=m \overrightarrow{v_{f}}-m \overrightarrow{v_{i}}$ (4)

Velocity (v) are vectors so direction matters, if positive direction is the right direction and negative direction left $\overrightarrow{v_{i}}=+3\, \frac{m}{s}$ and $\overrightarrow{v_{f}}=-3\, \frac{m}{s}$ so (4) becomes:

$\varDelta\overrightarrow{p}=m(-3\frac{m}{s}- (+3\frac{m}{s}))=-(10kg)(6\frac{m}{s})$

$\varDelta\overrightarrow{p}=-60\, \frac{mkg}{s}$ (5)

Using (5) on (3):

$\overrightarrow{F}_{avg}=\frac{-60\, \frac{mkg}{s}}{0.22s}$

$F_{avg}=272.73N$

8 0

4 years ago

A device for acclimating military pilots to the high accelerations they must experience consists of a horizontal beam that rotat

vladimir2022 [97]

Answer:

f = 0.4 Hz

Explanation:

The frequency of rotation of an object in order to achieve required centripetal or radial acceleration, can be found out by using the following formula:

f = (1/2π)√(ac/r)

where,

f = frequency of rotation = ?

ac = radial acceleration = 34.1 m/s²

r = radius = length of beam = 5.55 m

Therefore,

f = (1/2π)√[(34.1 m/s²)/(5.55 m)]

6 0

3 years ago

What is the main way in which heat transfer occurs in liquids and gases?

Taya2010 [7]

The answer is convection

7 0

3 years ago

Desde el balcón de un edificio se deja caer una manzana y llega a la planta baja en 5 s. ¿Desde qué piso se dejó caer, si cada p

miv72 [106K]

Answer: 42

Explanation:

I will answer this in English.

We know that the apple needs 5 seconds to reach the ground.

Each floor of the building has a height of 2.88m.

Now, when we drop something, the only force acting on the object is the gravitational one, so the acceleration of the apple is:

a = -g

for the velocity, we integrate the acceleration over time, and as the apple is dropped, we do not have any initial velocity, so we do not have a constant in the integration:

v = -g*t

for the position we integrate again, now we have an initial height H, so the position is:

p = (-g/2)*t^2 + H

now the apple hits the ground when p = 0, so we can solve this equation to find H.

i will use g = 9.8m/s^2

0 = (-4.9m/s^2)*(5s)^2 + H

H = 122.5 m

now knowing H, we can divide it by the height of a floor in the building and get the number of the floor.

N = 122.5m/2.88m = 42.5

this means that the apple was dropped in the floor 42 (the 0.5 means that the apple was not right where the floor 42 starts, it was dropped around the middle of the floor 42)

5 0

3 years ago

When asked how to create an electromagnet the best answer would be?

Ann [662]

Take wire and a nail strip 2 in of wire then wrap it around a nail

8 0

3 years ago

Sonny took 16 seconds to finish a 100-m race. What was Sonny's average speed in the race