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
svetoff [14.1K]
3 years ago
7

An object is dropped from 42m tall building. How long does It take to reach the ground?

Physics
1 answer:
yKpoI14uk [10]3 years ago
4 0

Answer:

It takes <u>2.93 s</u> for the object to reach ground from the height of 42 m.

Explanation:

Given:

Displacement of the object is, d=-42\ m

As it is dropped, initial velocity of the object is, u=0

Acceleration of the object is equal to acceleration due to gravity and is equal to, a=g=-9.8\ m/s^2

Now, using Newton's equation of motion and plugging in the values, we get:

d=ut+\frac{1}{2}at^2\\-42=0+\frac{1}{2}(-9.8)t^2\\-42=-4.9t^2\\t^2=\frac{-42}{-4.9}\\t^2=8.571\\t=\sqrt{8.571}=2.93\ s

So, it takes 2.93 s for the object to reach ground from the height of 42 m.

You might be interested in
A negative point charge - is at the center of a hollow insulating spherical shell, which has an inner radius R1 and an outer rad
Vaselesa [24]
The Explanation is Below

8 0
2 years ago
Describe two ways unbalanced forces help you in your day to<br> day life.
Alexxandr [17]

Answer:

  1. we need unbalance force to lift objects
  2. we need unbalance force to drag objects
6 0
3 years ago
A laser of wavelength 720 nm illuminates a double slit where the separation between the slits is 0.22 mm. Fringes are seen on a
kumpel [21]

Answer:

The appropriate solution is "2.78 mm".

Explanation:

Given:

\lambda = 720 \ nm

or,

  = 720\times 10^{-9} \ m

D=0.85 \ m

d = 0.22 \ mm

or,

  =0.22 \times 10^{-3} \ m

As we know,

Fringe width is:

⇒ \beta=\frac{\lambda D}{d}

hence,

Separation between second and third bright fringes will be:

⇒ \theta=\beta=\frac{\lambda D}{d}

       =\frac{720\times 10^{-9}\times 0.85}{0.22\times 10^{-3}}

       =2.78\times 10^{-3} \ m

or,

       =2.78 \ mm

8 0
2 years ago
True or False: A chemical reaction always happens when two substances are combined. (please help fast this is a test)
Makovka662 [10]

Answer:

no not always sometimes they react at all so false I hope I helped :)

6 0
2 years ago
Read 2 more answers
What is one result of meiosis?
Nonamiya [84]
Hello,

It's D! hope I helped.
8 0
3 years ago
Other questions:
  • A 50 g ball of clay traveling at speed v0 hits and sticks to a 1.0 kg block sitting at rest on a frictionless surface. part a wh
    7·1 answer
  • What is the Scientific definition of friction?
    13·2 answers
  • During a free fall Swati was accelerating at -9.8m/s2. After 120 seconds how far did she travel? Use the formula =1/2 * t2 to so
    15·2 answers
  • A flea jumps by exerting a force of 1.09 ✕ 10−5 N straight down on the ground. A breeze blowing on the flea parallel to the grou
    7·1 answer
  • Imagine whirling a ball on a string over you head. Suppose the knot holding the ball comes loose and the ball is instantly relea
    14·1 answer
  • Which type or types of motion is particle motion in surface waves?
    10·1 answer
  • Does anyone know the answers to these ?
    7·2 answers
  • An astronaut weighs 200 N on the Moon where gravity is 1.62 m/s/s. Find his weight on Earth. HELP PLEASE FAST
    7·1 answer
  • Please help I'm almost done.
    6·2 answers
  • A donkey pulls a crate up a rough, inclined plane at constant speed. Which one of the following statements concerning this situa
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!