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
Helga [31]
3 years ago
9

A car starts from rest and accelerates uniformly to reach a speed of 21 m/s in 7.0 s. What was the speed of the object after 2.0

seconds?
Physics
1 answer:
frosja888 [35]3 years ago
8 0

Answer:

6 m/s

Explanation:

Well we can find acceleration a=v/t = (21-0)/7=3 m/s^2

vf=at+v0, use this equation to solve for the vf

vf=3(2)+0=6 m/s was its speed at 2s

You might be interested in
What is the difference between uniform and non-uniform magnetic field lines?
timurjin [86]
Uniform magnetic lines as the name suggests are composed of lines that point to the same direction and of the same magnitude. This means all of these lines exert the same force. Non-uniform relates to different directions of the lines and a varied magnitude.
8 0
3 years ago
Two water balloons of mass 0.75 kg collide and bounce off of each other without breaking. Before the collision, one water balloo
bagirrra123 [75]
By the law of momentum conservation:-
=>m¹u¹ + m²u² = m1v1 + m²v² {let East is +ve}
=>u¹ + u² = v¹ + v² {as m1=m2}
=>3.5 - 2.75 = v1-1.5
<span> =>v¹ = 2.25 m/s (East) </span>
5 0
3 years ago
4. A bullet of mass 30 g is fired from a rifle of mass 5kg at a speed of 259m/s. 
Ostrovityanka [42]

Answer:

Rifle Momentum=7.77kg*m/s v'= 1.554 m/s

Explanation:

a) m1v1 + m2v2 = m1v1' + m2v2'

0+0 = 0.03*259 + P(rifle momentum)

solve for P

p= 7.77kg*m/s

b) 7.77= 5*v'

v'= 1.554 m/s

8 0
3 years ago
What is the acceleration caused by gravity on earth
arlik [135]

Answer:

Explanation:

It's 9.8 m/s^2

4 0
3 years ago
Energy is always conserved. It cannot be created or destroyed. It can, however, be transferred between objects or systems, from
sweet-ann [11.9K]

Have in mind: Energy is always conserved and, (...) be transferred between objects or systems, from one form to another.

Hence, the true relation is C, when a system gains kinetic energy, it loses potential energy.

Think about this,

K + P = constant

If K increases, then P need to decreases to holds the above relation.

5 0
3 years ago
Other questions:
  • A gas at 5.00 atm pressure was stored in a tank during the winter at 5.0 °C. During the summer, the temperature in the storage a
    6·1 answer
  • An electron moving with a velocity v= 5.0 × 107 m/s i enters a region of space where perpendicular electric and a magnetic field
    6·1 answer
  • On an essentially frictionless, horizontal ice rink, a skater moving at 3.0 m/s encounters a rough patch that reduces her speed
    5·1 answer
  • What is the IMA of the following pulley system?<br><br>34567
    12·1 answer
  • The answer pleaseeeeeee
    9·1 answer
  • A 4 kg block has a coefficient of friction of 0.3 between itself and the surface
    9·1 answer
  • For anyone taking the Velocity and Acceleration Quick Check, Here are the answer.s!
    5·1 answer
  • Which of the following is an example of a behavioral adaptation?
    5·1 answer
  • Question 4 (5 points)
    15·2 answers
  • Inductive charging is used to wirelessly charge electronic devices ranging from toothbrushes to cell phones. Suppose the base un
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!