Answer:
Either D or C
Both of these masks are used for dust, but since half masks are generally cheaper and easier to use, I'd go with C.
If this is correct, I'd appreciate a brainliest.
Answer:
d) 1 volt
Explanation:
The allowable range is 1 volt. The allowed tolerance (deviation from nominal) depends on what the nominal voltage is.
Answer:
The second classmate is right.
Explanation:
The height of first summit provides the potential energy it will use to climb the following ones.
Ep = m * g * h
Where
m: mass
g: acceleration of gravity
h: height
When the train goes downwards the potential energy is converted into kinetic energy (manifested as speed) and when it climbs it consumes its kinetical energy. As long as no summit is taller than the first the train should have enough energy to climb them.
Also it must be noted that friction also consumes energy, and if the track is too lomg all the energy might be consumed by it.
Answer:
t = 30.1 sec
Explanation:
If the ant is moving at a constant speed, the velocity vector will have the same magnitude at any point, and can be decomposed in two vectors, along directions perpendicular each other.
If we choose these directions coincident with the long edge of the paper, and the other perpendicular to it, the components of the velocity vector, along these axes, can be calculated as the projections of this vector along these axes.
We are only interested in the component of the velocity across the paper, that can be calculated as follows:
vₓ = v* sin θ, where v is the magnitude of the velocity, and θ the angle that forms v with the long edge.
We know that v= 1.3 cm/s, and θ = 61º, so we can find vₓ as follows:
vₓ = 1.3 cm/s * sin 61º = 1.3 cm/s * 0.875 = 1.14 cm/s
Applying the definition of average velocity, we can solve for t:
t =
= 
⇒ t = 30.1 sec