Metal
Explanation:
semiconductors are materials which have a conductivity between conductors (generally metals)
Answer:The reading on the scale is 64.76kg
Explanation:
According to Newton's 3rd law,when a person exerts a force on a plane,the plane simultaneously exerts a force equal in magnitude and opposite.
Given: mass=70kg ,alpha= 22.3°
Mg=mg×cos alpha= 70kg× cos22.3°=
70× 0.9252= 64.76kg
The reading on the scale is 64.76kg
Answer:
Distance covered by the sound in air is 800 meter and the time taken by the sound in water for the same distance is 0.5 seconds.
Explanation:
Given:
Speed of sound in air = 320 m/s
Speed of sound in water = 1600 m/s
Time taken to reach certain distance in air = 2.5 sec
a.
We have to find the distance traveled by sound in air.
Distance = Product of speed and time.
⇒
⇒
⇒ meters.
b.
Now we have to find how much time the sound will take to travel in water.
⇒ Time = Ratio of distance and speed
⇒
⇒ <em> ...distance = 800 m and speed = 1600 m/s</em>
⇒
⇒ seconds.
Distance covered by the sound in air is 800 meter and the time taken by the sound in water for the same distance is 0.5 seconds.
Answer:
5.71 m/s ;
20 m/s
Explanation:
Blue car:
At time, t = 0 ; Initial position = 20 m
Final position, = 60m after 4 seconds
The velocity = change in distance / change in time.
Velocity of blue = (60 - 20)m ÷ ((4 + 3) - 0),
Velocity of blue car = 40 / 7
= 5.71 m/s
Red car:
Initial Position = 0 ; final Position = 60
Time taken = 3 seconds
Velocity of Red car = (60 - 0)m ÷ 3
Velocity of Red car = 60 / 3
= 20 m/s