A rock resting on the top of a hill has POTENTIAL energy, while a rock
rolling down a hill has KINETIC energy.
We can use kinematics here if we assume a constant acceleration (not realistic, but they want a single value answer, so it's implied). We know final velocity, vf, is 1.0 m/s, and we cover a distance, d, of 0.47mm or 0.00047 m (1m = 1000mm for conversion). We also can assume that the flea's initial velocity, vi, is 0 at the beginning of its jump. Using the equation vf^2 = vi^2 + 2ad, we can solve for our acceleration, a. Like so: a = (vf^2 - vi^2)/2d = (1.0^2 - 0^2)/(2*0.00047) = 1,064 m/s^2, not bad for a flea!
Answer:bowling ball has greater kinetic energy
Explanation:
Kinetic energy of bowling ball:
mass=m=5kg
Velocity=v=6m/s
Kinetic energy =ke
Ke=0.5 x m x v x v
Ke=0.5 x 5 x 6 x 6
Ke=90J
Kinetic energy of ship:
mass=m=120000kg
velocity=v=0.02m/s
Ke=0.5 x m x v x v
Ke=0.5 x 120000 x 0.02 x 0.02
Ke=24J
Answer:
Explanation:
Suppose the distance between the two cities is D and the velocity in calm weather is V . The total time taken in two way travel is given by
Total distance / velocity
= 2 D / V
Suppose velocity of wind is v . Then in one way the velocity of airplane will become V + v and in the return trip its velocity will be V - v
Total time taken
= 
= 
= 
= 
= The denominator contains a factor
which is less than one so time calculated will be more than
2D / V
Hence in the second case time taken will be more .
Answer:
given,
mass of copper = 100 g
latent heat of liquid (He) = 2700 J/l
a) change in energy
Q = m Cp (T₂ - T₁)
Q = 0.1 × 376.812 × (300 - 4)
Q = 11153.63 J
He required
Q = m L
11153.63 = m × 2700
m = 4.13 kg
b) Q = m Cp (T₂ - T₁)
Q = 0.1 × 376.812 × (78 - 4)
Q = 2788.41 J
He required
Q = m L
2788.41 = m × 2700
m = 1.033 kg
c) Q = m Cp (T₂ - T₁)
Q = 0.1 × 376.812 × (20 - 4)
Q = 602.90 J
He required
Q = m L
602.9 = m × 2700
m =0.23 kg
