All categories

2 years ago

22. A ball is thrown horizontally from the roof of a building 12 m tall with a speed of 3.1 m/s.

Physics

1 answer:

zysi [14]2 years ago

5 0

Answer:

a) t = 1.6 s

b) d = 4.9 m

c) v = 16 m/s

d) θ = 79°

Explanation:

time of fall

t = √(2h/g) = √(2(12)/9.8) = 1.5649... s

d = vt = 3.1(1.56) = 4.8512...

vertical velocity vy = at = 9.8(1.56) = 15.336... m/s

v = √(15.336² + 3.1²) = 15.6464... m/s

θ = arctan(15.336/3.1) = 78.5724...°

You might be interested in

A ball thrown vertically upward is caught by the thrower after 2.00 s. Find (a) the initial velocity of the ball and (b) the max

ankoles [38]

Answer:

a) 9.8 m/s

b) 4.9 m

Explanation:

This problem is a good example of Vertical motion, where the main equations for this situation are:

$y=y_{o}+V_{o}t-\frac{1}{2}gt^{2}$ (1)

$V^{2}={V_{o}}^{2}-2gy$ (2)

Where:

$y$ is the height of the ball at a given time

$y_{o}=0m$ is the initial height of the ball (assuming the hand of the thrower the origin of the system)

$V_{o}$ is the initial velocity of the ball

$V$ is the final velocity of the ball

$t=2s$ is the time it takes for the ball to make the complete movement (from the moment it is thrown until it falls back into the pitcher's hands)

$g=9.8 m/s^{2}$ is the acceleration due to gravity

Knowing this, let's begin with the answers:

<h3>a) Initial velocity </h3>

In order to find the initial velocity $V_{o}$ of the ball, we will use equation (1) and $t=2s$ , taking into account that $y=0 m$ and $y_{o}=0m$ at this given time:

$0=0+V_{o}t-\frac{1}{2}gt^{2}$ (3)

Isolating $V_{o}$ :

$V_{o}=\frac{1}{2}gt$ (4)

$V_{o}=\frac{1}{2}(9.8 m/s^{2})(2 s)$ (5)

Then:

$V_{o}=9.8 m/s$ (6)

<h3>b) Maximum height </h3>

In this part, we will use equation (2), knowing the value of the height is maximum when $V=0$ . So, we will name this height as $y_{max}$ :

$0={V_{o}}^{2}-2gy_{max}$ (7)

Isolating $y_{max}$ :

$y_{max}=\frac{{V_{o}}^{2}}{2g}$ (8)

$y_{max}=\frac{{(9.8 m/s)}^{2}}{2(9.8 m/s^{2})}$ (9)

Finally:

$y_{max}=4.9 m$

4 0

3 years ago

Supposed an object is weighted with a spring balance, first in air then while totally immersed in water.The readings on the bala

Sedbober [7]

Is An object completely submerged in a fluid displaces its own volume of fluid ". This is: D

8 0

2 years ago

The stopping distances associated with slower speeds approximate the forward visibilities provided by low beam lights. However,

aleksandr82 [10.1K]

Answer:

a. True

Explanation:

Illumination distance is the distance, up to which the light of the vehicle can reach. Hence, it is a maximum distance from the, that driver can see.

Stopping distance is the minimum distance required by the car to stop after brakes are applied.

So, in order to avoid any accident the illumination distance must be greater than the stopping distance. So, the driver can stop the vehicle in time, when he sees something in front of it.

Since, the stopping distance in this case is two or three times longer than illumination distance. Therefore, low beam light does not provide enough visibility in high speed driving situations.

Hence, the correct option is:

<u></u>

5 0

3 years ago

Which area of earth is most similar to the suns convention zone

julsineya [31]

The area of the Earth that is most similar to the Sun's convection zone would be the mantle. The convection zone of the sun is its outermost layer where heat transfer by convection happens which is similar to the Earth's mantle. It would be the crust because it is the outer most layer.

3 0

2 years ago

What is the mass of a rock lifted 2 meters off the ground that has 196 J of potential energy?

eimsori [14]

Answer:

10kg

Explanation:

Let PE=potential energy

PE=196J

g(gravitational force)=9.8m/s^2

h(change in height)=2m

m=?

PE=m*g*(change in h)

196=m*9.8*2

m=10kg

4 0

3 years ago