T = 3.5 secs
Velocity (v) = g * t = 10 m/s^2 * 3.5 sec = 35 m/s
Answer:
Explanation:
We know that Impulse = force x time
impulse = change in momentum
change in momentum = force x time
Force F = .285 t -.46t²
Since force is variable
change in momentum = ∫ F dt where F is force
= ∫ .285ti - .46t²j dt
= .285 t² / 2i - .46 t³ / 3 j
When t = 1.9
change in momentum = .285 x 1.9² /2 i - .46 x 1.9³ / 3 j
= .514i - 1.05 j
final momentum
= - 3.1 i + 3.9j +.514i - 1.05j
= - 2.586 i + 2.85j
x component = - 2.586
y component = 2.85
Answer:
Explanation:
The cross product of two vectors is given by

Where, θ be the angle between the two vectors and \widehat{n} be the unit vector along the direction of cross product of two vectors.
Here, K x i = - j
As K is the unit vector along Z axis, i is the unit vector along X axis and j be the unit vector along axis.
The direction of cross product of two vectors is given by the right hand palm rule.
So, k x i = j
j x i = - k
- j x k = - i
i x i = 0
<span>7.7 m/s
First, determine the acceleration you subject the sled to. You have a mass of 15 kg being subjected to a force of 180 N, so
180 N / 15 kg = 180 (kg m)/s^2 / 15 kg = 12 m/s^2
Now determine how long you pushed it. For constant acceleration the equation is
d = 0.5 A T^2
Substitute the known values getting,
2.5 m = 0.5 12 m/s^2 T^2
2.5 m = 6 m/s^2 T^2
Solve for T
2.5 m = 6 m/s^2 T^2
0.41667 s^2 = T^2
0.645497224 s = T
Now to get the velocity, multiply the time by the acceleration, giving
0.645497224 s * 12 m/s^2 = 7.745966692 m/s
After rounding to 2 significant figures, you get 7.7 m/s</span>
F = m*a
30 N = (ma + mb) * a
30 = 5*a
a = 6 m/s ^2
F de B em A
30 - F de B,A = ma * a
30 - F de B em A = 3 * 6
30 - 18 = F de B em A
12 = F de B em A
Resposta: 6 m/s^2 e 12N
Bate com o gabarito, man? Ou eu tô viajando aqui?
Abç!