You fire a projectile at an angle along flat ground, giving it an initial horizontal velocity of 8.43 m/s and an initial vertical
velocity of 7.07 m/s.
(the resulting initial speed is vo = 11 m/s at an angle of
00 40 degrees above the horizontal)
How long is the projectile in the air? 1
=
х
S
What is the projectile's speed as it passes through the highest
point in its trajectory? -11
x m/s

Acarpenter is driving a 15.0-g steel nail into a board. his 1.00-kg hammer is moving at 8.50 m/s when it strikes the nail. half of the kinetic energy of the hammer is transformed into heat in the nail and does not flow out of the nail. what is the increase in temperature of the nail after the three blows that the carpenter needs to drive the nail in completely? the specific heat of steel is 448 j/kg ∙ k. a) 2.7 k b) 1.8 k c) 7.7 k d) 8.1 k e) 3.6 k