Kinetic energy = (1/2) (mass) (speed)²
BUT . . . in order to use this equation just the way it's written,
the speed has to be in meters per second. So we'll have to
make that conversion.
KE = (1/2) · (1,451 kg) · (48 km/hr)² · (1000 m/km)² · (1 hr/3,600 sec)²
= (725.5) · (48 · 1000 · 1 / 3,600)² (kg) · (km·m·hr / hr·km·sec)²
= (725.5) · ( 40/3 )² · ( kg·m² / sec²)
= 128,978 joules (rounded)
Answer:
D.The striking foot pushes backward against the ground. The friction with the ground provides an equal and opposite force forward
Note that
1 J = 0.239 cal
By definition,
Work = Force x Distance
Therefore work done is
W = (1 N)*(2000 m) = 2000 J
In calories,
W = (2000 J)*(0.239 cal/J) = 478 cal
Answer: 478 calories
Answer:
10581.59 V
Explanation:
We are given that
Magnetic field=B=0.65 T
Speed of electron=
Charge on electron, 
Mass of electron,
We have to find the potential difference in volts required in the first part of the experiment to accelerate electrons.

Where V=Potential difference
Mass of electron
v=Velocity of electron
Using the formula


Hence, the potential difference=10581.59 V