Kinetic energy of the horse and rider = 1/2 (mass) (speed)²
At 4.0 m/s : KE = 1/2 (55kg) (4 m/s)² = 440 joules
At 6.0 m/s : KE = 1/2 (55kg) (6 m/s)² = 990 joules
She increased the kinetic energy of herself and her vehicle by 550 joules,
so she must have put at least that much work into it.
Conductor because it creates heat.
Answer:
93.4 kg
Explanation:
Draw a free body diagram. There are three four forces:
Weight force mg pulling down,
Normal force N pushing up,
Friction force Nμ pushing left,
Applied force F pulling up and to the right, 30.0° above the horizontal.
Sum of forces in the y direction:
∑F = ma
N + F sin 30.0° − mg = 0
N = mg − ½ F
Sum of forces in the x direction:
∑F = ma
F cos 30.0° − Nμ = 0
½√3 F = Nμ
Substitute:
½√3 F = (mg − ½ F) μ
½√3 F / μ = mg − ½ F
½√3 F / μ + ½ F = mg
½F (√3 / μ + 1) = mg
m = F (√3 / μ + 1) / (2g)
Plug in values:
m = 410 N (√3 / 0.500 + 1) / (2 × 9.8 m/s²)
m = 93.4 kg
70 mph
= 70 * 1600 m/h
= <span>112000 m/h
-> 112000 m/h
= 112000 /3600 m/s
= 31.111... m/s
= <u>31 m/s (2s.f)</u></span>
Answer:
Taking a child away from their parents is awful, so taking your hand away from your body is awful.
I'm not sure if there were word choices for this particular question, but I do hope this helps!
