Đề thi chọn học sinh giỏi môn Vật lí Tiếng Anh 9 - Năm 2017- 2018 - PGD&ĐT Tiên Lãng (Có đáp án)

 UBND HUYỆN TIÊN LÃNG ĐỀ THI CHỌN HỌC SINH GIỎI
 PHÒNG GD - ĐT TIÊN LÃNG MÔN: VẬT LÍ TIẾNG ANH 9
 Năm học 2017 – 2018
 I. Complete the answer
Ex1: If the segment is like a drawing, where R1 = 4Ω ; R3 
 Rx
= 12Ω and the second circuit voltage is 14V. For the 
 A R1 B
power consumption on all 28w, the value of Rx value is: R3
 Answer:
Ex2: Resistor R1 = 3  , R2 = 6  in series, then connected to the power supply with 
a voltage of 4.5 V. Power consumption on resistor R2 is:
 Answer:
Ex3: A metal conductor of resistor R is cut into two equal segments, and then 
paralleled, the equivalent resistance is 10 Ω. The value of R is
 Answer:
Ex4: Resistor R1 = 4 ; R2 = 6 ; R3 = 12 parallel to each other. The equivalent 
resistance R of the circuit segment is
 Answer:
Ex5: For the circuit as shown: Know R1 = R2 = 12W, R3 
 R1
 R
= 6W. The equivalent resistance of the AB circuit is A 3 B
 Answer:
 R2
Ex6: Resistor R1= 10 withstand the maximum voltage 
set at its two ends is U1 = 6V. Resistor R2= 5 withstand the largest voltage set at its 
two ends is U2 = 4V. The circuit consisting of R1 and R2 in series with the largest 
voltage applied at both ends of this circuit is: Answer:
 Ex7: Place a needle magnet near the tube (see picture). What happens when we close 
 the K key?
 N S
 K _
 +
 Answer: 
 Ex8: Apply the left hand rule to determine the electromagnetic force acting on the 
 wire passing through the current (see below).
 I
 S + N
Ex9: Two resistors R1= 30 and R2= 60 in parallel to the voltage U = 120V. The 
power consumption of the parallel circuit is as follows:
 Answer:
Ex10: Simultaneously parallel two resistors R1= 30 ; R2= 20 to the circuit with a 
voltage of 30V. The current in the main circuit is:
 Answer:
 II. Answer Ex11 in English
Ex11: For side drawings:Lamp 1: 6V-12W, resistance V
R = 6Ω. Connect the power to the normal 2 lights, the 
 R B
voltmeter is only 12V. Calculate power on two lights? A
 C
 Đ2
Solusion
 Đ1 Answer
Ex1: If the segment is like a drawing, where R1 = 4Ω ; R3 
 Rx
= 6 Ω and the second circuit voltage is 14V. For the 
 A R1 B
power consumption on all 28w, the value of Rx value is: R3
 Answer: Rx= 6Ω
Ex2: Resistor R1 = 3  , R2 = 6  in series, then connected to the power supply with 
a voltage of 4.5 V. Power consumption on resistor R2 is:
 Answer: P1= 4Ω
Ex3: A metal conductor of resistor R is cut into two equal segments, and then 
paralleled, the equivalent resistance is 10 Ω. The value of R is
 Answer: 40Ω
Ex4: Resistor R1 = 4 ; R2 = 6 ; R3 = 12 parallel to each other. The equivalent 
resistance R of the circuit segment is
 Answer: 2Ω
Ex5: For the circuit as shown: Know R1 = R2 = 12W, R3 
 R1
 R
= 6W. The equivalent resistance of the AB circuit is A 3 B
 Answer: 12Ω
 R2
Ex6: Resistor R1= 10 withstand the maximum voltage 
set at its two ends is U1 = 6V. Resistor R2= 5 withstand the largest voltage set at its 
two ends is U2 = 4V. The circuit consisting of R1 and R2 in series with the largest 
voltage applied at both ends of this circuit is:
 Answer: 9 V
 Ex7: Place a needle magnet near the tube (see picture). What happens when we close 
 the K key? N S
 K _
 +
 Answer: The magnet is pushed by the 
 tube
 Ex8: Apply the left hand rule to determine the electromagnetic force acting on the 
 wire passing through the current (see below).
 I
 S + N
Ex9: Two resistors R1= 30 and R2= 60 in parallel to the voltage U = 120V. The 
power consumption of the parallel circuit is as follows:
 Answer:720W
Ex10: Simultaneously parallel two resistors R1= 30 ; R2= 20 to the circuit with a 
voltage of 30V. The current in the main circuit is:
 Answer: 2,5A
Ex11: For side drawings:Lamp 1: 6V-12W, resistance V
R = 6Ω. Connect the power to the normal 2 lights, the 
 R B
voltmeter is only 12V. Calculate power on two lights? A
 C
 Đ2
Solusion Đ1
Because a normal light 1 should:
U1=6v, P1=12W 
=> I1 =2A ; 
 U 6
 I 1 1A
 R R 6 
 I I 1 IR 3A I2 3A
We have U1 +U2=12v => U2 =6v
Calculate power on two lights is: P1=U2I2=6.3= 18W By Le Quoc Huy - THCS Dong Hung