Recent content by Sam Fred

Homework Statement Q) A transmission cable AB exerts a 3000N force on the pole in the direction of the tangent to the cable at A (see Fig. 1). Determine the required tension T in the wire AB if the resultant of the two forces at A is to be vertical (1 point). Find the magnitude R of the...

Homework Statement A spring AB or constant k = 2N/m is attached to a support A and to a collar of mass m=1kg. The unstretched length of the spring is 1m, Knowing that the collar is released from rest at x = x0 = 0.9 m and neglecting friction between the collar and the horizontal rod...

Thanks ...

I was wrong about P . P = 20 t → Impulse = ∫ p dt = 20 t2 /2 Thus P = 20 (4) / 2 = 40 N But isn't the friction impulse negative and thus we get 300 + 40 + 1000 - 519.6 = 100 v2 v2 =8.2 m/s ?

300 + 80 + 1000 - 519.6 = 100 v2 v2 = 8.6 m/s Shouldn't the friction be negative and what about the P , It is given P = 20 t , shouldn't i multiply it by t=2 twice ??

Aha ... mv1 + P t (dlta t) + mg sin 30 (dlta t) - mg cos 30 Mk (dlta t) = mv2 30 + 80 + 1000 + 519.6 = 100 v2 v2 = 5.9 m/s

Homework Statement The 100kg crate shown in Fig. 1 is acted upon by a force having a variable magnitude P = 20t N, where t is in seconds. Determine the crates’ velocity 2 seconds after P has been applied. The initial velocity is v1=3m/s down the plane, and the coefficient of kinetic...

So : m1v1 - Friction Force X Δt = m1v2 cos60 Friction Force = 5000 N ??

Homework Statement Assume that the athlete approaches the take-off line from the left with a horizontal velocity of 10m/s, remains in contact with the ground for 0.1s, and take off at a 60°angle with a velocity for 10m/s, determine (1) the vertical component of the average impulsive force...

Oh yes ... it was a typo Thanks very much for helping me through the problem

Aha ... I guess I was confused ... for train a which is going to the right m1v1 - F(avg from b) t = m2v3 F(avg from b) = (m1v1 - m2v3 ) / t F(avg from b) = 18750 N to the left

Ok... then : -m2v2 + F(avg) t = (m1+m2) v3 F(avg) = 28125 N

I solved the question , but i need to check it with you guys ... I believe there is something wrong with part b . Homework Statement The 15000kg train A is running at 1.5 m/s on the horizontal tack (to the right) when it encounters a 12000kg train B running at 0.75m/s toward it (to the...

aha ... thanks man ... but how would i know the speed off he slope ? Do i repeat the same steps with substituting t = 0.5 sec

Homework Statement The Track for this racing event was designed so that riders jump off the slope at 30°, from a height of 1m. During a race it was observed that the rider shown in Fig. 2 remained in mid air for 1s. Determine, 1) the speed at which he was traveling off the slope, ( 2points)...