Answer:
a) KA = 1.2 J
b) vB = 5.00 m/s
c) W = 6.30 J
Explanation:
m = 0.600 kg
vA = 2.00 m/s
KB = 7.50 J
a) KA = ?
b) vB = ?
c) W = ?
We can apply the folowing equations
K = 0.5*m*v²
and
W = ΔK = KB- KA
then
a) KA = 0.5*m*vA² = 0.5*(0.600 kg)*(2.00 m/s)²
⇒ KA = 1.2 J
b) KB = 0.5*m*vB² ⇒ vB = √(2*KB / m)
⇒ vB = √(2*7.50 J / 0.600 kg)
⇒ vB = 5.00 m/s
c) W = ΔK = KB- KA = (7.50 J) - (1.2 J)
⇒ W = 6.30 J
Answer:
P = W / t = m g s / t = m g v where work by auto = m g s
30 kw = 30000 watts = 30000 J / s
Work wasted = F v as shown above relating work and power
Work done against incline = m g s sin 8.75 and power against incline
= m g v sin 8.75 = 1222 v Joules / sec
power in moving auto = power available - power lost to friction
power in moving auto = 30000 - resistance = 30000 - 910 v
1222 v = 30000 - 910 v
v = 30000 / 2132 = 14 m/s
Note: constant resistance to motion must mean P = W / t = F s / t = F v
A person could push, pull or lift an object
Answer:
Plan B.
Because flexibility is best improved by stretching.
Explanation:
Improving and increasing flexibility is done by having stretching sessions daily which maintains and widens the range of motion in the joints and stretches muscles.
Answer:
rubber ball
Explanation:
basically friction is caused by little electrical bonds at a molecular level. the ice had more bonds due to it being a cube rather than a ball which has one point of contact. this means less energy is needed to put the ball in motion than the ice cube.