The initial velocity of the car is 11 m/s.
Explanation:
- Here, we can use the equations of motions.
- The first of equation of motion is v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time.
- The given parameters are,
Final velocity, v = 20 m/s
acceleration of the care, a = 2 m/
time, t = 3 s
Initial velocity, u = ?
- Hence, the equation can be written as u = v - at
once you substitute all these vales, you will get u = 11 m/s
Answer:
0.56 m/s
Explanation:
The speed of the head at the end of the interval in each case is the area under the acceleration curve. Then the difference in speeds is the difference in areas.
We can find the area geometrically, using formulas for the area of a triangle and of a trapezoid.
A = 1/2bh . . . . area of a triangle
A = 1/2(b1 +b2)h . . . . area of a trapezoid
If h(t) is the acceleration at time t for a helmeted head, the area under that curve will be (in units of mm/s) ...
Vh = 1/2(h(3)·3) +1/2(h(3) +h(4))·1 +1/2(h(4) +h(6))·2 +1/2(h(6))·1
Vh = 1/2(4h(3) +3h(4) +3h(6)) = 1/2(4·40 +3·40 +3·80) = 260 . . . mm/s
If b(t) is the acceleration for a bare head, the area under that curve in the same units is ...
Vb = 1/2(b(2)·2 +1/2(b(2) +b(4))·2 +1/2(b(4) +b(6))·2 +1/2(b(6)·1)
Vb = 1/2(4b(2) +4b(4) +3b(6)) = 1/2(4·120 +4·140 +3·200) = 820 . . . mm/s
Then the difference in speed between the bare head and the helmeted head is ... (0.820 -0.260) m/s = 0.560 m/s
Answer:
0
Explanation:
It’s before the projectile was fired, so nothing has happened yet.
Sound waves can combine to become bigger. true
When one is using a psychrometer and the reading of the two temperatures are almost or nearly the same values, you can say that the air has a high relative humidity that is the humidity is near the saturation point. Hope this answers the question.