Answer
Hi,
correct answer is {D} 3.5 m/s²
Explanation
Acceleration is the rate of change of velocity with time. Acceleration can occur when a moving body is speeding up, slowing down or changing direction.
Acceleration is calculated by the equation =change in velocity/change in time
a= {velocity final-velocity initial}/(change in time)
a=v-u/Δt
The units for acceleration is meters per second square m/s²
In this example, initial velocity =2.0m/s⇒u
Final velocity=44.0m/s⇒v
Time taken for change in velocity=12 s⇒Δt
a= (44-2)/12 = 42/12
3.5 m/s²
Best Wishes!
Answer:
Explanation:
Impulse = change in momentum
mv - mu , v and u are final and initial velocity during impact at surface
For downward motion of baseball
v² = u² + 2gh₁
= 2 x 9.8 x 2.25
v = 6.64 m / s
It becomes initial velocity during impact .
For body going upwards
v² = u² - 2gh₂
u² = 2 x 9.8 x 1.38
u = 5.2 m / s
This becomes final velocity after impact
change in momentum
m ( final velocity - initial velocity )
.49 ( 5.2 - 6.64 )
= .7056 N.s.
Impulse by floor in upward direction
= .7056 N.s
Answer:
<em>The Answer is both B and C, </em><em>since it has same options from the question given. Gear, slow her vehicle in a lower</em>
Explanation:
<em>The use of a lower gear in a vehicle helps a person to control their speed limits, when approaching a hill. it also saves the brakes too, using the brakes down a hill can overheat the gear and causes brake failures</em>
<em>By changing in into a lower gear and also letting the engine to do the brake work in a vehicle, the engine will absorb a force and slow the vehicle down, but in most cases brakes can be applied but with lesser pressure.</em>
<em>In this case Stella need to slow down by applying her lower gear down a hill to avoid accidents on the road, by controlling her speed limits and for safety precaution</em>
-0 m/s
- average velocity=displacement/time
- the runners displacement is zero so her average velocity must be zero
