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
motikmotik
3 years ago
14

Imagine a rock is dropped from the top of a tall building. After 2 seconds of falling, the rock’s instantaneous speed is approxi

mately 20m/s. does anyone know is it true or false
Physics
2 answers:
pshichka [43]3 years ago
6 0

Answer:

TRUE

Explanation:

As we know that stone is falling freely from rest

so here we can use kinematics to find the final speed of the stone

v_f = v_i + at

here we know that

v_i = 0

a = 9.81 m/s^2

t = 2 s

now we have

v_f = 0 + (9.81)(2)

v_f = 19.62 m/s

so final speed of the rock is nearly 20 m/s

shepuryov [24]3 years ago
3 0
True
It's in free fall( 9.8 m/s), 2 seconds have passed.
You might be interested in
Help !!!! Estimate the number of breaths taken by a person during 44 years?
Lisa [10]
44 x 12. I got the 12 from the total of 12 months in a year.


44 > 40

x
12 > 10
----------
The way my teacher taught me how to estimate is look at the neighbor to 44 and 12. The only time 44 can become 50, is when the neighbor is 5 or up. Same thing for 12. Now, multiply 40 and 10.

40 x 10 = 400.

Therefore, your estimate is 400.

The real answer is 520 breaths.
6 0
3 years ago
Without heat from the Sun, the water cycle would A) reverse. B) not work. C) slow down. D) not be affected.
Tanzania [10]
B) not work ,because the water would freeze
4 0
3 years ago
Read 2 more answers
Which is a complete sentence?
8_murik_8 [283]

It takes a noun and a verb to make a complete sentence.
There isn't a single verb in  a),  b), or  c).
"Affords" is the verb (predicate) in d)., the only complete sentence.
 
6 0
3 years ago
Read 2 more answers
The bulk modulus of water is 2.2 x 109 Pa, and its density is 1.0 x 103 kg/m3. What is the speed of sound in water?
yarga [219]

hi guys! Lets be friends!

7 0
3 years ago
William WangHomework #33 Regents Review (3)0989Assignment Mode : Open (Time On Task) 9 of 25 ListenDuring a collision, an 84-kil
Lemur [1.5K]

Answer:

1.7\cdot 10^3 N

Explanation:

The impulse theorem states that the product between the force and the time interval of the collision is equal to the change in momentum:

F \Delta t = m \Delta v

where

F is the force

\Delta t is the time interval

m is the mass

\Delta v is the change in velocity

Here we have

m = 84 kg

\Delta t = 1.2 s

\Delta v = 24 m/s

So we can solve the equation to find the force:

F= \frac{m \Delta v}{\Delta t }=\frac{(84 kg)(24 m/s)}{1.2 s}=1680 N \sim 1.7\cdot 10^3 N

4 0
3 years ago
Other questions:
  • A single-engine helicopter has two rotors; a main rotor and a tail rotor. The main rotor has a diameter of 14.4 m and rotates at
    9·1 answer
  • PLS I NEED HELP ASAP!!!
    10·1 answer
  • A series circuit has a capacitor of 0.25 × 10−6 F, a resistor of 5 × 103 Ω, and an inductor of 1 H. The initial charge on the ca
    10·1 answer
  • Will give brainliest! how does an engineer use physical science?
    10·1 answer
  • If the vertical posts supporting these wires divide the lines into straight 19.0 m segments, what magnetic force does each segme
    15·1 answer
  • In a cyclotron, the orbital radius of protons with energy 300 keV is 16.0 cm . You are redesigning the cyclotron to be used inst
    15·2 answers
  • Coal burns in a furnace, producing light and heat. This reaction is
    9·2 answers
  • A bullet of 5 gm is fired from a pistol of 1.5 kg. If the recoil velocity of pistol is 1.5 m/s,
    6·1 answer
  • A certain superconducting magnet in the form of a solenoid of length 0.56 m can generate a magnetic field of 6.5 T in its core w
    10·1 answer
  • Derive the dimension of coefficient of linear expansivity
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!