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
Tresset [83]
3 years ago
11

Your annoying little brother is dropping rocks out of his bedroom window on the 2nd floor. You are on the ground floor and watch

a rock fall past the patio door onto the ground below. In this problem, ignore air resistance. If the rock takes 0.28 s to cross the 2.3-m-high glass door, from what height above the top of the door was it dropped?
Physics
1 answer:
Valentin [98]3 years ago
5 0

Answer:

Too little information, please elaborate

You might be interested in
The blades in a blender rotate at a rate of 6800 rpm . When the motor is turned off during operation, the blades slow to rest in
tangare [24]
The angular acceleration of the blade when it's switched off is (-6800 rev/min) divided by (2.8 sec) = -2,428.6 rev/(min-sec) = -40.5 rev/sec^2 .
5 0
3 years ago
A train slows down as it rounds a sharp horizontal turn, going from 94.0 km/h to 46.0 km/h in the 17.0 s that it takes to round
Svetllana [295]

Answer:

1.41 m/s^2

Explanation:

First of all, let's convert the two speeds from km/h to m/s:

u = 94.0 km/h \cdot \frac{1000 m/km}{3600 s/h} = 26.1 m/s

v=46.0 km/h \cdot \frac{1000 m/km}{3600 s/h}=12.8 m/s

Now we find the centripetal acceleration which is given by

a_c=\frac{v^2}{r}

where

v = 12.8 m/s is the speed

r = 140 m is the radius of the curve

Substituting values, we find

a_c=\frac{(12.8 m/s)^2}{140 m}=1.17 m/s^2

we also have a tangential acceleration, which is given by

a_t = \frac{v-u}{t}

where

t = 17.0 s

Substituting values,

a_t=\frac{12.8 m/s-26.1 m/s}{17.0 s}=-0.78 m/s^2

The two components of the acceleration are perpendicular to each other, so we can find the resultant acceleration by using Pythagorean theorem:

a=\sqrt{a_c^2+a_t^2}=\sqrt{(1.17 m/s^2)+(-0.78 m/s^2)}=1.41 m/s^2

6 0
3 years ago
Read 2 more answers
A cross-country skier can complete a 7.5 km race in 45 min. What is the skier’s average speed?
kap26 [50]

Answer:

Speed = 10 km/hr

Explanation:

Speed = Distance / Time

Since we have to convert it into minutes to hours ( because it is km/hr )

45 minutes = 0.75 hours

Therefore,

Speed = 7.5 / 0.75

           = <u>10 km/hr </u>

<u></u>

<u>Hope it helps!</u>

3 0
3 years ago
Explain the relationship between velocity and acceleration. Are these scalar or vector quantities?
stiv31 [10]
A scalar is something that only has speed without a DIRECTION while a vector has direction. acceleration is a vector and mass is a scalar.
4 0
3 years ago
Read 2 more answers
All but one of the following is an important component of soil.
viktelen [127]
Air is the answer i do believe
4 0
3 years ago
Read 2 more answers
Other questions:
  • You could use an elevator or the stairs to lift a box to the tenth floor.which has greater power?why?
    11·2 answers
  • Oceanography in a sentence
    5·2 answers
  • A 650 × 10–4 F capacitor stores 24 × 10–3 of charge.
    13·1 answer
  • 102) Consider massive gliders that slide friction- free along a horizontal air track Glider A has a mass of 1 kg, aspeed of 1 m/
    5·1 answer
  • If the temperature is held constant during this process and the final pressure is 683 torrtorr , what is the volume of the bulb
    15·1 answer
  • A ball of mass m = 4.6 kg, at one end of a string of length L= 6.6 m, rotates in a vertical circle just fast enough to prevent t
    11·1 answer
  • Which of the following do waves carry?
    15·1 answer
  • Which of the following statements about the conservation of momentum is not correct? Momentum is conserved for a system of objec
    7·1 answer
  • Which of the following are used in an electrochemical cell?
    11·1 answer
  • 10. In Freudian theory, which one of the following is an example of a Thanatos instinct, which includes aggression, trauma, and
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!