All categories

2 years ago

(b) A ball is thrown vertically upwards with

Physics

1 answer:

harina [27]2 years ago

6 0

Answer:

5 seconds

Explanation:

The vertical position of the ball will be given by the equation

df = do + vo t + 1/2 a t^2 df = final position = 0 ( on the ground

do = original position ( 25 m )

vo = original velocity (+ 20 m/s)

a = - 10 m/s^2

So this becomes

0 = 25 + 20 t - 1/2 (10)t^2

= - 5 t^2 +20 t + 25 Use Quadratic Formula a = -5 b=20 c = 25

to find the positive value of t = 5 seconds

You might be interested in

Is position a base or derived quantity?

amid [387]

Position is measured in meters (m), so it is a base quantity.

<h3>What is base quantity?</h3>

A base or fundamental quantity is a physical quantity, in which other quantities are derived from.

Example of fundamental quantities;

Mass
Length (position)
Time
Temperature
Amount of substance

<h3>What is a derived quantity?</h3>

Derived quantities are those quantities obtained or expressed from fundamental quantities.

Example of derived quantities;

Speed
Acceleration
Volume
Area
Density, etc

Thus, we can conclude that position measured in meters (m) is a base quantity.

Learn more about base quantities here: brainly.com/question/14480063

#SPJ1

8 0

2 years ago

Brainliest for correct answer :)

Novosadov [1.4K]

Answer:

Explanation:

The answer is b that is the final speed - initial speed divided by the time taken

Please mark as brainliest

6 0

3 years ago

Read 2 more answers

If a sound is 30 dB and its absolute pressure was 66 x 10-9 Pa, what must have been the reference pressure?

Ksenya-84 [330]

Given:

I = 30dB

P = 66 × $10^{-9}$ Pa

Solution:

Formula used:

I = $20\log_{10}(\frac{P}{P_{o}})$ (1)

where,

I = intensity of sound

P = absolute pressure

$P_{o}$ = reference pressure

Using Eqn (1), we get:

$30 = 20\log _{10}\frac{66\times 10^{-9}}{P^{o}}$

$P_{o}$ = $\frac{66\times 10^{-9}}{10^{1.5}}$

$P_{o}$ = 2.08 × $10^{-9}$ Pa

4 0

4 years ago

A crane with output power of 200W will lift a 600N object a vertical distance of 4.0 meters in seconds

Finger [1]

<span>1 w = 1N/s the change in total energy =mgh = 600*4 = 2400N. 2400N/200N/s = 12seconds </span>

8 0

3 years ago

If a wave's third harmonic has a frequency of 24 Hz, what is its

Charra [1.4K]

Answer:

8 Hz, 48 Hz

Explanation:

The standing waves on a string (or inside a pipe, for instance) have different modes of vibrations, depending on how many segments of the string are vibrating.

The fundamental frequency of a standing wave is the frequency of the fundamental mode of vibration; then, the higher modes of vibration are called harmonics. The frequency of the n-th harmonic is given by

$f_n = nf_1$