Mechanics | Relativity Answers

a particle moves along a straight line such that its displacement at any time t given by s=( t cube-6 t square-3t+4) meters .the velocity when the acceleration is zero is ?????????????

a man moves in an open field such that after moving 10m on a straight line , he makes a sharp turn of 60 degree to his left . the total displacement after 8 such turn is equal to ??????????????

a particle travels half of the distance of a straight journey with speed 6m/s .the remaining part of distance is covered with speed 2m/s for half of the time of remaining journey and with speed 4m/s for the other half of time .the average speed of the particle is ??????????

Two points x1 and x2 at x = 0 and x = 1 m are observed. The transverse motion of the two points are found to be as follows:
y1(x,t)=0.2 sin 3πt
and y2(x,t)=0.2 sin (3πt + π/8)
Calculate the frequency, wavelength and speed of the wave.

A small object is released from rest and falls 1.00 × 102 feet near the surface of the earth. Neglect air resistance.

How long will it take to fall through the 1.00 × 102 feet mentioned?



3.12 s



4.50 s



2.49 s



6.25 s



10.0 s

A runner hopes to complete the 10,000-m run in less than 30.0 min. After exactly 25.0min , there are still 1900m to go. The runner must then accelerate at 0.25m/s2 for how many seconds in order to achieve the desired time?
Express your answer using two significant figures.

A jogger runs along a straight and level road for a distance of 8.0 km and then runs back to her starting point. The time for this roundtrip is 2.0 h. Which one of the following is true?

if we reach at the centre than our weight is?

1km/m=how much m/s

A worker drops a wrench from the top of a tower 87.0 m tall. What is the velocity when the wrench strikes the ground?