1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Zina [86]
3 years ago
6

Imagine a rock is dropped from the top of a tall building.After 2 seconds of falling the rock is instantaneous speed In approxim

ately 20m/s
Physics
1 answer:
Fantom [35]3 years ago
8 0

This is True.

Explanation:

initial velocity= Vi=0

final velocity= V

acceleration due to gravity= 9.8 m/s²

using the kinematic equation V= Vi+gt

V=0+(9.8)(2)

V= 19.6 m/s which is approximately equal to 20 m/s

Thus after 2 seconds, the instantaneous speed of the rock is approximately 20 m/s.

You might be interested in
The aeroplane lands at a speed of 80 m/s
strojnjashka [21]

The mass of the aeroplane is 300,000 kg.

<h3>What is Newton's second law of motion?</h3>

It states that the force F is directly proportional to the acceleration a of the body and its mass.

The law is represented as

F =ma

where acceleration a = velocity change v / time interval t

Given is the aeroplane lands at a speed of 80 m/s. After landing, the aeroplane takes 28 s to decelerate to a speed of 10 m/s. The mean resultant force on the aeroplane as it decelerates is 750 000 N.

The force expression will be

F = mv/t

Substitute the values and we have

750000 = m x  (80 -10)/ 28

750,000 = m x 2.5

m = 300,000 kg

Thus, the mass of the aeroplane is 300,000 kg.

Learn more about Newton's second law of motion.

brainly.com/question/13447525

#SPJ1

8 0
2 years ago
The small currents in axons corresponding to nerve impulses produce measurable magnetic fields. a typical axon carries a peak cu
Gemiola [76]

Answer:

6.66\cdot 10^{-12}T

Explanation:

The magnetic field produced by a current-carrying wire is given by

B=\frac{\mu_0 I}{2\pi r}

where

\mu_0 is the vacuum permeability

I is the current

r is the distance from the wire

In this problem we have

I=0.040 \mu A=4\cdot 10^{-8}A

r = 1.2 mm = 0.0012 m

So the magnetic field strength is

B=\frac{(4\pi \cdot 10^{-7} H/m)(4\cdot 10^{-8}A)}{2\pi (0.0012 m)}=6.66\cdot 10^{-12}T

5 0
3 years ago
A potato and raisins salad has been warmed up to a temperature of 80∘C80∘C and let it stand for three minutes. Then one tries a
barxatty [35]

Answer : The correct option is, (a) No. Potatoes will be warmer.

Explanation :

Formula used :

Q=m\times c\times \Delta T

where,

Q = heat taken

m = mass of substance

c = specific heat of substance = ?

\Delta T = change in temperature

As we are given that the potatoes have a specific heat of 3430J/(kg^oC) and raisins have a specific heat of 1630J/(kg^oC). That means higher the value of specific heat the more heat taken by the substance (more warmer will be the substance). So, the potatoes will be more warmer as compared to raisins.

Hence, the correct option is, (a) No. Potatoes will be warmer.

6 0
3 years ago
When is a hypothesis formed in the process of conducting an experiment?
tangare [24]
Because you need to have a guess to know what to argue or explain in your experiment
7 0
3 years ago
Bruno the bat flies at a speed of 0.5 m/s in circle of radius 1 m. What is his acceleration?
beks73 [17]

Answer:

Acceleration is 0.25m/s^2

Explanation:

Given the following :

Speed = 0.5m/s

Radius(r) of circle = 1m

Acceleration round a circular path is given as :

a = v^2 / r

Where

a = acceleration of the body

v = speed / velocity

r = radius

Therefore,

a = v^2 / r

a = (0.5)^2 / 1

a = 0.25m/s^2

7 0
3 years ago
Other questions:
  • Which best explains why a wood burning fireplace represents an open system
    13·2 answers
  • Visible light shining through a window is an example of _____.
    9·2 answers
  • If a particle undergoes shm with amplitude 0.21 m, what is the total distance it travels in one period?
    11·1 answer
  • Two tuning forks having frequencies of 460 and 464 Hz are struck simultaneously. What average frequency will you hear, and what
    11·1 answer
  • Saturn has a radius of about 9.0 earth radii, and a mass 95 times the Earth’s mass. Estimate the gravitational field on the surf
    15·2 answers
  • A spring has a equilibrium length of 10.0 cm. When a force of 40.0 N is applied to the spring, the spring has a length of 14.0 c
    6·1 answer
  • How many cups of water should you drink in a day?
    5·1 answer
  • The sizes of most of the cells our bodies are about A.1micrometer
    14·2 answers
  • Since astronauts in orbit are apparently weightless, a clever method of measuring their masses is needed to monitor their mass g
    7·1 answer
  • Clinical psychologists are concerned with everyday problems of adjustment.<br> True<br> False
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!