Vladimir1023456789

17.04.2021 04:56

Физика

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A. 3.0 km

B. 3.8 km

C. 4.0 km

D. 5.0 km

[1]

2. A car is stationary at traffic lights. When the traffic lights go green, the driver presses down sharply on the accelerator. The resultant horizontal force acting on the car varies with time as shown.

Which graph shows the variation with time of the speed of the car?

[1]

3. A micrometer screw gauge is used to measure the diameters of two cylinders.

Diameter of the first cylinder = 12.78 ± 0.02 mm

Diameter of the second cylinder = 16.24 ± 0.03 mm

The difference in the diameters is calculated. What is the uncertainty in this difference?

A ±0.01mm

B ±0.02mm

C ±0.03mm

D ±0.05mm

[1]

4. A piece of a metal ball weighs 1.0 N in alcohol and 1.4N in air. The density of the metal is 2.5 g−3 .Calculate the density of the alcohol in g−3 .

A. 0.56

B. 0.40

C. 0.84

D. 0.48 [1]

5. What volume of water will escape per minute from an open-top tank through an opening 3.0 cm in diameter that is 5.0 cm below the water level in the tank shown?

A. 0.42 3

B. 9.90 3

C. 0.42 3

D. 9.90 3

[1]

6. A horizontal pipe shown below has the following dimensions: the cross-sectional area of the narrow part P is 7.0 2 and the wide part q is 21.0 2. The velocity of the liquid in P section is 3 times the velocity in section Q. What can be said about the speed of water flow in the different sections of the pipe?

A. The speed of water flow in section P is the same as the speed of water flow in Q.

B. The speed of water flow in section Q is 9 times the speed of water flow in P

C. The speed of water flow in section Q is 3 times the speed of water flow in P

D. The speed of water flow in section P is 3 times the speed of water flow in Q