Home » Posts tagged 'projectile motion' (Page 2)
Tag Archives: projectile motion
Discuss a circumstance in which angle between velocity and acceleration is less than 90.
Discuss a circumstance in which angle between velocity and acceleration lies batween 180 and 90.
(Hifsa Zafar asked this)
In projectile motion when the object is moving up, the angle between velocity and acceleration (due to gravity g) is between 90 degree and 180 degree.
during the downward motion of a projectile, the angle between velocity and acceleration is between 0 and 90 degree.
- A particle travels 20 m in 7th second and 24m in 9th sec. find initial velocity?
- in a projectile motion , a body thrown from the ground ,at what angle both the vertical height and range will be equal?
- The velocity v(cm/s) of a particle is given in terms of time t(in seconds) by the equation v = at+b/t+c. Dimension of a,b, and c are ?
“A ball is projected vertically upwards with an initial velocity of 28m/s and is observed to pass a point 30m above the projection point,at what 2times does the ball pass these points?”
(Vimal Raj Answered)
ans : 1.356 sec and 1.444 sec .
from v=u+at we get t=2.8 . (time taken to reach the max height )
fm v2-u2=2aS we get S=39.2 m (max height reached)
observer at 30 m .
so , in btw distance btw observer and ball (at the top) =9.2 m
at top ball is at rest and time taken to reach the observer can be calculaed from S=ut + 1/2 at2 ,we get t=1.356s .
and next time can be calculated by 2.8 – 1.356 =1.444 sec .
(The answer has not been scrutinized. If any error, teachers and visitors can post as comment)
“A body is projected with velocity u with an angle with the horizontal. What is its average velocity when it crosses half of its max height”
One side of the roof of a building slopes up at 33.5°. A roofer kicks a round, flat rock that has been thrown onto the roof by a neighborhood child. The rock slides straight up the incline with an initial speed of 15.0 m/s. The coefficient of kinetic friction between the rock and the roof is 0.430. The rock slides 10.0 m up the roof to its peak. It crosses the ridge and goes into free fall, following a parabolic trajectory above the far side of the roof, with negligible air resistance. Determine the maximum height the rock reaches above the point where it was kicked.
(The question is left for visitors to answer.)