Answer:
Force in the rocket will be 4166.64 N
Explanation:
We have given mass of the rocket m = 3 kg
Rocket acquires a speed of 50 m sec so final speed v = 50 m/sec
Initial speed u = 0 m/sec
Distance traveled s = 90 cm = 0.9 m
From third equation of motion we know that 


From newton's law we F = ma
So force will be 
So force in the rocket will be 4166.64 N
Answer:
d
Explanation:
good question. now the bus is moving in constant velocity . a student in front tosses a ball to the student in back. but we dont know the speed at which the student tosses a ball. we have to assume the speed
assume the speed of ball is slightly less than the speed of bus. in this case the stationary observer sees the ball in slower speed than the one inside the bus.
so a is correct
now assume the speed of ball is 1/2 the speed of bus. here stationary observer sees the ball the same speed as the one in bus observe
b is correct
assume the speed of ball is very small than the speed of bus . in this case the stationary observer see in grater speed than the student in bus
e also correct
so correct answer is d. it depends on the speed of ball tossed by the student in front.
Answer:
125÷2= 62.5 is your average speed. If the train was resting it's not moving your going nowhere . If the train is traveling at constant speed in a straight line it's speed will increase going through mountains will slow it down. if the train is coming to a braking force its speed will decrease
we can reduce the friction between its moving parts.
Answer:
0.149 s or 0.15 s
Explanation:
let initially ball is moving towards left hence initial velocity = - 28.62 m/s
final velocity as ball moves right = +20 m/s
force = rate of change in momentum
force = mass × change in velocity / time
or time = mass × change in velocity / force
time = 2× ( 20 -( -28.62)) / 652.36
time = 2× ( 20 +28.62)) / 652.36
time = 2× 48 .62/652.36
time = 0.149 s or 0.15 s