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
xenn [34]
3 years ago
13

Help me please!! 15points

Physics
1 answer:
Romashka-Z-Leto [24]3 years ago
4 0

Explanation:

Acceleration is the change in speed over change in time.

a = Δv / Δt

a. The car's acceleration is:

a = (80 km/h − 0 km/h) / 10 s

a = 8 km/h/s

So every second, the speed increases by 8 km/h.

b. The cyclist's acceleration is:

a = (16 m/s − 4.0 m/s) / 5.6 s

a = 2.1 m/s²

c. The stone's speed is:

10.0 m/s² = (v − 0 m/s) / 3.5 s

v = 35 m/s

d. The time is:

1.6 m/s² = (10 m/s − 0 m/s) / t

t = 6.3 s

You might be interested in
An electric motor rotates 60 times per second if the alternating current source is 60 Hz. How many times will an electric motor
valentina_108 [34]

Answer:

180,000

Explanation:

Frequency is a quantity that is measured in Hertz [Hz] and it represents the number of rotations per second.

A motor with a frequency of 50 Hz will rotate 50 times per second.

Since we don't want to know how many times it rotates per second, but per hour. The first step is to find how many seconds there are in an hour and then multiply that amount by 50.

Seconds in an hour:

there are 60 seconds per minute, and 60 minutes per hour, thus there are

60*60 = <u>3,600 seconds in an hour</u>

We know that the motor will rotate 50 times per second so to find the number of rotations in 1 hour =  3,600 seconds we multiply:

50*3,600 = 180,000 rotations

8 0
3 years ago
Which equation is true of an atom with no elctrical charge
Paladinen [302]

Answer:

Atoms are composed of electrons (charge -1), protons (charge +1), and neutrons (no charge). So in a neutral atom the correct answer is "D".

3 0
2 years ago
Alex swims at an average speed of 45m/min. how far does he swim in 1 min 24 sec?
saveliy_v [14]

Answer:

63 m

Explanation:

Average speed of swimming = 45 m/min

Time = 1 minute 24 seconds

Converting time into minutes:

Formula:

Putting values, we get.

Thus, Alex swims for 63 m in 1 minute and 24 seconds.

6 0
3 years ago
Which statement about elements and atoms is true?
Vika [28.1K]
Atoms are the smallest unit of an element
8 0
3 years ago
What is the focal length of a lens
goldenfox [79]

Answer:

The focal length of a lens is refers to the distance from the center of the lens to the principal foci.

4 0
3 years ago
Other questions:
  • How much is one degree Celsius in temperature change ?
    9·1 answer
  • The image shows a diagram. which descriptions best fit the labels
    14·2 answers
  • Which two ways can light be understood
    5·1 answer
  • G A dragster starts from rest and accelerates at 35 m/s2 m / s 2 . How fast is it going after t t
    11·1 answer
  • Consider an airplane modeled after the twin-engine Beechcraft Queen Air executive transport. The airplane has the following char
    8·1 answer
  • A carbon rod with a radius of 2.1 mm is used to make a resistor. The resistivity of this material is 3.2 × 10−5 Ω · m. What leng
    11·1 answer
  • We wrap a light, nonstretching cable around a 10.0 kg kg solid cylinder with diameter of 38.0 cm cm . The cylinder rotates with
    11·1 answer
  • The fact that, in general, liquids and gases expand when heated
    13·1 answer
  • When two ocean plates move away from each other that is called?
    11·1 answer
  • The chart below lists the densities of various gemstones. If a gemstone has a mass of 6.24 g and a volume of 1.98 cm cubed, whic
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!