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
astraxan [27]
3 years ago
14

A Rocket is launched and reaches a height of 72m before falling back to Earth a) What was it's take off velocity? b) What was it

's final velocity when it landed? c) What was it's velocity at the highest point?​
Physics
1 answer:
DerKrebs [107]3 years ago
4 0

Answer:

Answers are in the explanation

Explanation:

a)

vf² = vi² + 2gh

0 = vi² + 2(-9.8)(72)

vi = 37.57 m/s

b)

vf = vi + gt

0 = 37.57 - (9.8)t

t = 3.83 s

3.83 x 2 = 7.67 s

vf = vi + gt

vf = 37.57 - (9.8)(7.67)

vf = -37.60 m/s

c)

Its vertical velocity at the highest point is 0 m/s

You might be interested in
The magnetic field strength at the north pole of a 2.0-cmcm-diameter, 8-cmcm-long Alnico magnet is 0.10 TT. To produce the same
horrorfan [7]

Answer:

2653 turns

Explanation:

We are given that

Diameter,d=2 cm

Length of magnet,l=8 cm=8\times 10^{-2} m

1m=100 cm

Magnetic field,B=0.1 T

Current,I=2.4 A

We are given that

Magnetic field of solenoid and magnetic are same and size of both solenoid and magnetic are also same.

Length of solenoid=8\times 10^{-2} m

Magnetic field of solenoid

B=\frac{\mu_0NI}{l}

Using the formula

0.1=\frac{4\pi\times 10^{-7}\times 2.4\times N}{8\times 10^{-2}}

Where \mu_0=4\pi\times 10^{-7}

N=\frac{0.1\times 8\times 10^{-2}}{4\pi\times 10^{-7}\times 2.4}=2653 turns

6 0
2 years ago
A 5.5-kW resistance heater in a water heater runs for 3 hours to raise the water temperature to the desired level. Determine the
Stella [2.4K]

Answer:

16.5 kwh and 59400 kJ.

Explanation:

kWh is a measure of energy that is equivalent to the power in kw times the number of hours the device worked.

In this case, it would be equal to:

E_{kwh}=5.5kw*3h=16.5kwh

1 kw also means 1kj of energy spent per second. With this, we calculate the amount of energy in kJ spent by the resistance:

E_{kJ}=5.5\frac{kJ}{s}*3h*\frac{3600s}{1h} = 59400 kJ

5 0
3 years ago
Consider three scenarios in which a particular box moves downward under the pull of gravity :
luda_lava [24]

Answer:

1. True  WA > WB > WC

Explanation:

In this exercise they give work for several different configurations and ask that we show the relationship between them, the best way to do this is to calculate each work separately.

A) Work is the product of force by distance and the cosine of the angle between them

    WA = W h cos 0

   WA = mg h

B) On a ramp without rubbing

     Sin30 = h / L

     L = h / sin 30

     WB = F d cos θ  

     WB = F L cos 30

     WB = mf (h / sin30) cos 30

     WB = mg h ctan 30

C) Ramp with rubbing

    W sin 30 - fr = ma

   N- Wcos30 = 0

   W sin 30 - μ W cos 30 = ma

    F = W (sin30 - μ cos30)

   WC = mg (sin30 - μ cos30) h / sin30

   Wc = mg (1 - μ ctan30) h

When we review the affirmation it is the work where there is rubbing is the smallest and the work where it comes in free fall at the maximum

Let's review the claims

1. True The work of gravity is the greatest and the work where there is friction is the least

2 False. The job where there is friction is the least

3 False work with rubbing is the least

4 False work with rubbing is the least

5 0
3 years ago
To determine the height of a flagpole, Abby throws a ball straight up and times it. She sees that the ball goes by the top of th
Kryger [21]

Answer:

H = 10.05 m

Explanation:

If the stone will reach the top position of flag pole at t = 0.5 s and t = 4.1 s

so here the total time of the motion above the top point of pole is given as

\Delta t = 4.1 - 0.5 = 3.6 s

now we have

\Delta t = \frac{2v}{g}

3.6 = \frac{2v}{9.8}

v = 17.64 m/s

so this is the speed at the top of flag pole

now we have

v_f - v_i = at

17.64 - v_i = (-9.8)(0.5)

v_i = 22.5 m/s

now the height of flag pole is given as

H = \frac{v_f + v_i}{2}t

H = \frac{22.5 + 17.64}{2} (0.5)

H = 10.05 m

5 0
2 years ago
What do measurements of the number of neutrinos emitted by the Sun tell us about conditions deep in the solar interior?
OverLord2011 [107]

Answer:

The neutrinos are produced in the core of the sun by nuclear fusion and measuring their number helps us confirm that there are enough proton-proton chain reactions of each which produce a neutrino and going on in the Sun's core to explain the energy output of the Sun.

4 0
3 years ago
Other questions:
  • An engine performs 6400 j of work on a motorbike the motorbike and the rider have a combined mass of 200 kg if the bike started
    11·1 answer
  • When he sees teachers encouraging other children to wait in the cafeteria until the first bell rings, Ian follows them. What typ
    11·2 answers
  • According to Oxford Dictionaries, a spit take is an act of suddenly spitting out liquid one is drinking in response to something
    6·1 answer
  • If there is motion, then a force in acting true or false
    7·1 answer
  • You notice that heat is released during a chemical reaction. This reaction is a(n) _______ reaction. endothermic heat hot exothe
    11·1 answer
  • I need help!!!! I don’t understand physical science at all.
    13·1 answer
  • You are tasked with calibrating the springs for a pinball machine. Your method of testing the springs is by attaching masses ont
    14·1 answer
  • At which point is potential energy greatest?
    7·1 answer
  • Please help today exam
    15·1 answer
  • After the big bang occurred, the universe
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!