Answer:
a
Explanation:
The most reasonable conclusion of the above phenomenon is that water is a poor conductor of heat. Basically water is an insulator. The heat from surface to the bottom of the beaker will take a lot of time. Moreover, no convection current is formed so, heat might not even reach the bottom surface. Hydrogen bonding also play a vital role in determining the thermal properties of water.
hence option A is correct
Answer:
Heat required to raise the temperature of the aluminium is 4750 J
Explanation:
As we know that the heat energy required to raise the temperature of the aluminium is given as

here we know that
m = 50 g


so we have


Answer:
3420.39 N
Explanation:
Applying,
Fd = 1/2(mv²-mu²)................. Equation 1
Where F = force on the bumber, d = distance, m = mass of the car, v = final velocity, u = initial velocity.
make F the subject of the equation
F = (mv²-mu²)/2d............... Equation 2
From the question,
Given: m = 890 kg, v = 0 m/s (to rest), u = 1.4 m/s, d = 0.255 m
Substitute these values into equation 2
F = [(890×0²)-(890×1.4²)]/(2×0.255)
F = -1744.4/0.51
F = -3420.39 N
The negative sign denotes that the force in opposite direction to the motion of the car.
Answer:
Explanation:
The relation between orbital period T and orbital radius R is as follows .
T² ∝ R³
T ∝ R¹°⁵
So time period of orbit is proportional to radius of orbit . Higher the height , larger the orbital period . As the orbital period is larger than required , the altitude of satellite must have been larger than required .
As mass of satellite is not involved in the formula of orbital period , this is independent of mass of the satellite .
Hence the option C is correct .
Answer:
the answer would be d foresure