Answer:
Explanation:
Mass of nails is 0.25kg
Mass of hammer 5.2kg
Speed of hammer is =52m/s
Then, Ben kinetic energy is given as
K.E= ½mv²
K.E= ½×5.2×52²
K.E= 7030.4J
Given that, two-fifth of kinetic energy is converted to internal energy
Internal energy (I.E) = 2/5 × K.E
Internal energy (I.E) = 2/5 × 7030.4
I.E=2812.16J.
Energy increase is total Kinetic energy - the internal energy
∆Et= K.E-I.E
∆Et= 7030.4 - 2812.16
∆Et= 4218.24J
We use the formula,

Here, h is the variable represents the height of the flare in feet when it returns to the sea so, h = 0 and u is the initial velocity of the flare, in feet per second and its value of 192 ft/sec.
Substituting these values in above equation, we get
.
Here, t= 0 neglect because it is the time when the flare is launched.
Thus, flare return to the sea in 12 s.
A) experiment. Is the answer.
hypothesis is the educated guess about what the result of the experiment is before conducting the experiment.
Observation is what you see and record during the experiment.
i think its very hot summers
The answer is either c or d but c is the best answer