Answer:
Height = 0.25 metres
Speed = 3.26 m/s
Explanation:
Kinetic energy = 17 joules
Mechanical energy = 25
Potential energy = 25-27 = 8
Potential energy PE = m*g*h
8 = 3.2x9.81xh
8 = 31.392h
We divide through by the value of h to get height
8/31.392 = h
h = 0.25 metres
We solve for speed = velocity
Kinetic Energy = 1/2mv²
17 = 0.5x3.2xV²
17 = 1.6v²
V² = 17/1.6
V² = 10.625
V = √10.625
Velocity = 3.26m/s
3s
Explanation:
Given parameters:
Mass of car = 1000kg
Force applied = 8000N
speed = 24m/s
Unknown:
time taken for the car to stop = ?
Solution:
According to newton's second law of motion; "the force on a body is the product of its mass and acceleration".
Force = mass x acceleration
let us find the acceleration of the car;
a = = = 8m/s²
since the car is accelerating at a rate of 8m/s², when the brakes are applied, it will start decelerating at the constant rate, - 8m/s²
Applying the appropriate equation of motion;
V = U + at
V is the final velocity
U is the initial velocity
a is the acceleration
t is the time taken
final velocity = 0
0 = U + at
-U = at
-24 = -8t
t = 3s
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Newton's laws brainly.com/question/11411375
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Answer:
When an object is speeding up, the acceleration is in the same direction as the velocity. Thus, this object has a positive acceleration. In Example B, the object is moving in the negative direction (i.e., has a negative velocity) and is slowing down