Answer:
Average speed = 1.2 m/s
Average velocity = 0.4 m/s
Explanation:
Average speed = total distance/total time
Average speed = (40 + 20)/(40 + 10)
Average speed = 60/50
Average speed = 1.2 m/s
Average velocity = displacement/time
Now, she ran 40 m south and ran 20 m back north which is in the direction of where she began the journey.
Thus;
Displacement = 40 - 20 = 20 m
Average velocity = 20/50 = 0.4 m/s
Answer:
both magnitude and direction
Explanation:
When an object moves in a circular path, its motion is called uniform circular motion. In this motion, the force acting on it is centripetal force and it is moving under centripetal acceleration. This type of force acts towards the centre of the circle.
In this type of motion, the speed remains constant while the velocity keeps on changing. The object's centripetal acceleration remains constant in magnitude as well as direction.
Hence, the correct option is (3).
Answer: K-core , 1s orbital
Explanation: Electron of Hydrogen atom has lowest energy
when it is in K core (1s-orbital)
Answer:
Negative work done of 30729.6 Joules
Explanation:
Since work done is dot product of force and displacement. so,
W= F.d
W= F d cosΘ
where Θ is the angle between force and displacement. Since resistive force and displacement makes an angle of 180 (as one is pointed east and other west). So,
W = (7.92)(1940)(cos (180)) (distance should be in meter)
W = 15364.8(-1)
W = -15364.8 (for going east)
Total work done will be twice of that as the resistive force and distance are same for the way back.
W = -15364.8 + (-15364.8)
W = -30729.6 Joules
Answer:
117,30m
Explanation:
I think the situation here is a horizontal projection to the ground. So in order to find the distance the formula = Ut, where U is the initial speed and t is the Time of flight. To get the time of flight in this case =√2h/g where h is the height and g is gravity. so to get the time = √2×300÷9.81 =7.821 .so range =ut which is equal to the time multiplied by 15m/s =117.30m
