D :P ? kakskekwksmajsoeowlskw
x+7
------------------- =
x^2+4x -21
x+7
= -------------------
(x+7)(x-3)
1
= ---------- where x is not equal -7 and 3
x - 3
answer is A. first choice
Answer:
108,000 joules
Step-by-step explanation:
Kinetic energy, k = 1/2 mv^2
Where,
m = mass of the object in kilogram
v = velocity in meters per seconds
If
Velocity of an object = 20 meters per seconds
Kinetic energy = 48,000 joules
Solve for m
k = 1/2 mv^2
48,000 = 1/2 × m × 20^2
48,000 = 1/2 × m × 400
48,000 = 200m
m = 48,000 / 200
m = 240 kg
If it speeds up to 30 meters per second, then what is its new kinetic energy?
k = 1/2 mv^2
Using m = 240 kg
k = 1/2 mv^2
= 1/2 × 240 × 30^2
= 1/2 × 240 × 900
= 216,000 / 2
= 108,000 joules
The new kinetic energy = 108,000 joules
