Answer:
Skateboard
Explanation:
Acceleration is change in velocity over time.
a = Δv / Δt
The airplane's acceleration is:
a = (1005 km/h − 1000 km/h) / 10 s
a = 0.5 km/h/s
The skateboard's acceleration is:
a = (5 km/h − 0 km/h) / 1 s
a = 5 km/h/s
Answer: 
Explanation:
Given
Wavelength of light 
Screen is
away
Distance between two adjacent bright fringe is 
When same experiment done in water, wavelength reduce to 
So, the distance between the two adjacent bright fringe is 
Keeping other factor same, distance becomes

Answer:
The kaleidoscope
Explanation:
gives a number of images formed by reflection from the mirrors inclined to one another. Designers and artists use kaleidoscope to get ideas for new patterns to design wallpapers, jewellery and fabrics.
When hot tea is mixed to chilled coke, tea loses heat and coke gains heat. Thus, tea cools down but coke gets heated. Because it is liquid and liquid does not totally cool down to the ambient temperature, it and the iced drink will eventually reach the same temperature.