1. What is meant by half-life?

A tennis player tosses a tennis ball straight up and then catches it after 1.77 s at the same height as the point of release.

Alex_Xolod [135]

(a) The acceleration of the ball while it is in flight has a magnitude of 9.81 m/s2 in downward direction.

(b) The velocity of the ball when it reaches its maximum height is zero.

(c) The initial velocity of the ball is 17.36 m/s.

(d) The maximum height it reaches is 15.36 m.

<h3>Acceleration of the ball</h3>

The acceleration of the ball while it is in flight has a magnitude of 9.81 m/s2 in downward direction.

<h3>Velocity of the ball at maximum height</h3>

The velocity of the ball decreases as the ball moves upwards and eventually becomes zero at maximum height.

<h3>Initial velocity of the ball</h3>

v = u - gt

at maximum height, final velocity, v = 0

0 = u - gt

u = gt

u = 9.81 x 1.77

u = 17.36 m/s

<h3>Maximum height reached by the projectile</h3>

h = ut - ¹/₂gt

h = 17.36(1.77) - ¹/₂(9.81)(1.77²)

h = 15.36 m

Thus, the acceleration of the ball while it is in flight has a magnitude of 9.81 m/s2 in downward direction.

The velocity of the ball when it reaches its maximum height is zero.

The initial velocity of the ball is 17.36 m/s.

The maximum height it reaches is 15.36 m.

Learn more about maximum height here: brainly.com/question/12446886

#SPJ1

3 0

2 years ago

The energy of a photon is E=\frac{hc}{\lambda}E = h c λ where c is the speed of light and h is a constant known as Planck's cons

Basile [38]

Answer: As a red photon has a twice of the wavelegth to the violet photon then the red photon has half energy of the violet photon.

Explanation: In order to explain the above statement we have to consider the Plack postulate where the energy of photons depend directely of the frequency . As the wavelength and frequency are related by :

c= λ*υ c is the speed of light, λ is the wavelength and υ the frequency of the photon

so the energy of photons are inversely proportional to the wavelength.

As a consequence twice wavelengtht means half energy for the photon.

5 0

3 years ago

Help me solve this please

Leto [7]

Since it's a projectile being launched the only force acting upon it is gravity, since the object is in free fall once it's launched

so to calculate time you'd utilize the general formula of
$xf = xi + vxi(t) + \frac{1}{2} (a) {t}^{2}$
and then solve using time and make it into the y axis, so change the x's to y's, which will change a to g.
since Vyi is always usually 0, you can drop that out of this equation so the formula to find time would be
$t = \sqrt{ \frac{2(y)}{g} }$
So you'll plug in and it'll be
$t = \sqrt{ \frac{2( - 49m)}{ - 9.81 \frac{m}{s {}^{2} } } }$
to find the maximum height you'll have to do some trigonometry to solve it.
To make it easier draw a triangle
put the 60° mark as shown in the picture.
Then you'll need to find the hypotenuse or horizontal to find the vertical
So the hypotenuse would be the 113m/s
so then you'll use
$\ \sin( 60) = ( \frac{o}{h})$

plug in the numbers
$113( \ \sin (60) ) = o$
now that you have the vertical

use the formula
${vf}^{2} = {vi}^{2} + 2gd$
solve for d which will give you the hypotenuse
$d = { (-vertical \frac{m}{s} )}^{2} \div 2( - 9.81 \frac{m}{ {s}^{2} } )$
The "vertical" is what you found in the previous step.
Vf^2 is equal to 0 so you can just drop that number out since it's 0
then once you have that then youre not done yet
since you're on a cliff of 49 m you'll have to add 49m to the previous answer that you found d to find the maximum height.

I hope this helps!

6 0

3 years ago

Why do we use the name electromagnetism to describe the force of an

ElenaW [278]

Answer:

magnet, gravity

Explanation:

5 0

3 years ago

Technician A says that you can usually depressurize a brake accumulator by turning the ignition switch ""off"" to disable the el

Rzqust [24]

Answer:

Both Technician A and Technician B

Explanation:

In order to gain a better understanding of the solution above let define some terms

Break Accumulator

We can define a break accumulator as storage that that helps generate the required pressure in order for the breaking system to respond faster this accumulator is charged by turning the steering wheel slowly at once from lock to lock now this build the pressure in the accumulator and one way to depressurize is it is by turning the ignition switch ""off""

Now a scan tool is a device that can interface with a car it can also be used to diagnose a car an get the diagnostic information to help in the cars diagnoses and also be used to reprogram a car

3 0

3 years ago