Power
Q. If a person lifts a 10 kg object to a height of 5 m in 2 seconds, what is the power exerted?
A.
25 W
B.
50 W
C.
75 W
D.
100 W
Show solution
Solution
First, calculate the work done: W = mgh = 10 kg * 9.8 m/s² * 5 m = 490 J. Then, P = W/t = 490 J / 2 s = 245 W.
Correct Answer: B — 50 W
Learn More →
Q. If a person lifts a 10 kg weight to a height of 2 meters in 4 seconds, what is the power exerted?
A.
50 W
B.
100 W
C.
200 W
D.
250 W
Show solution
Solution
First, calculate the work done: W = mgh = 10 kg * 9.8 m/s² * 2 m = 196 J. Then, power is P = W/t = 196 J / 4 s = 49 W, approximately 50 W.
Correct Answer: B — 100 W
Learn More →
Q. If a person lifts a 50 kg box to a height of 2 meters in 5 seconds, what is the power exerted?
A.
200 W
B.
400 W
C.
500 W
D.
600 W
Show solution
Solution
The work done against gravity is W = mgh = (50 kg)(9.8 m/s²)(2 m) = 980 J. Power is P = W/t = 980 J / 5 s = 196 W, approximately 200 W.
Correct Answer: B — 400 W
Learn More →
Q. If a person lifts a 50 kg object to a height of 2 meters in 5 seconds, what is the power exerted?
A.
200 W
B.
400 W
C.
500 W
D.
600 W
Show solution
Solution
The work done is W = mgh = 50 kg * 9.8 m/s^2 * 2 m = 980 J. Power is W/t = 980 J / 5 s = 196 W, approximately 200 W.
Correct Answer: B — 400 W
Learn More →
Q. If a person lifts a weight of 100 N to a height of 2 m in 4 seconds, what is the power exerted?
A.
50 Watts
B.
100 Watts
C.
200 Watts
D.
25 Watts
Show solution
Solution
Work done = Force × Distance = 100 N × 2 m = 200 J. Power = Work / Time = 200 J / 4 s = 50 W.
Correct Answer: A — 50 Watts
Learn More →
Q. If a^3 = 27, then the value of a is?
Show solution
Solution
Taking the cube root of both sides, a = 27^(1/3) = 3.
Correct Answer: C — 3
Learn More →
Q. If a^3 = 27, what is the value of a?
Show solution
Solution
Since 27 = 3^3, we have a = 3.
Correct Answer: C — 3
Learn More →
Q. If x^3 - 8 = 0, what is the value of x?
Show solution
Solution
x^3 = 8 => x = 2
Correct Answer: A — 2
Learn More →
Q. If x^3 = 8, then the value of x is?
Show solution
Solution
Taking the cube root of both sides, x = 8^(1/3) = 2.
Correct Answer: A — 2
Learn More →
Q. If x^4 = 81, what is the value of x?
Show solution
Solution
Taking the fourth root, x = 81^(1/4) = 3.
Correct Answer: A — 3
Learn More →
Q. In a hydraulic lift, if the input power is 2000 W and the output power is 1800 W, what is the efficiency of the lift?
A.
90%
B.
80%
C.
70%
D.
75%
Show solution
Solution
Efficiency is calculated as (Output Power / Input Power) * 100%. Here, efficiency = (1800 W / 2000 W) * 100% = 90%.
Correct Answer: B — 80%
Learn More →
Q. In a hydraulic lift, if the input power is 500 W and the efficiency is 80%, what is the output power?
A.
400 W
B.
500 W
C.
600 W
D.
700 W
Show solution
Solution
Output power can be calculated using the formula: Output Power = Efficiency * Input Power. Here, Output Power = 0.8 * 500 W = 400 W.
Correct Answer: A — 400 W
Learn More →
Q. In an electric circuit, if the voltage is 12 V and the current is 3 A, what is the power?
A.
36 W
B.
9 W
C.
4 W
D.
12 W
Show solution
Solution
Power in an electric circuit is given by P = V * I. Here, P = 12 V * 3 A = 36 W.
Correct Answer: A — 36 W
Learn More →
Q. In an electric circuit, if the voltage is doubled while the resistance remains constant, what happens to the power?
A.
It remains the same
B.
It doubles
C.
It quadruples
D.
It halves
Show solution
Solution
Power in an electric circuit is given by P = V^2/R. If V is doubled, P becomes (2V)^2/R = 4V^2/R, which is quadrupled.
Correct Answer: C — It quadruples
Learn More →
Q. The value of (x^2)^3 is equal to?
A.
x^5
B.
x^6
C.
x^7
D.
x^8
Show solution
Solution
Using the power of a power property, (a^m)^n = a^(m*n), we get (x^2)^3 = x^(2*3) = x^6.
Correct Answer: B — x^6
Learn More →
Q. What is the relationship between power, force, and velocity?
A.
P = F * v
B.
P = F / v
C.
P = F + v
D.
P = F - v
Show solution
Solution
Power is defined as the product of force and velocity in the direction of the force, given by P = F * v.
Correct Answer: A — P = F * v
Learn More →
Q. What is the relationship between power, voltage, and current in an electrical circuit?
A.
P = V/I
B.
P = VI
C.
P = V + I
D.
P = V - I
Show solution
Solution
In an electrical circuit, power is given by the formula P = VI, where P is power, V is voltage, and I is current.
Correct Answer: B — P = VI
Learn More →
Q. What is the SI unit of power?
A.
Joule
B.
Watt
C.
Newton
D.
Pascal
Show solution
Solution
Power is defined as the rate at which work is done or energy is transferred. The SI unit of power is the Watt (W), which is equivalent to one Joule per second.
Correct Answer: B — Watt
Learn More →
Q. What is the value of (2^3) * (2^2)?
A.
2^5
B.
2^6
C.
2^7
D.
2^8
Show solution
Solution
Using the property of exponents, (2^3) * (2^2) = 2^(3+2) = 2^5.
Correct Answer: A — 2^5
Learn More →
Q. What is the value of (4^2) * (4^3)?
A.
64
B.
128
C.
256
D.
1024
Show solution
Solution
4^2 * 4^3 = 4^(2+3) = 4^5 = 1024
Correct Answer: C — 256
Learn More →
Q. What is the value of (x^2)^3?
A.
x^5
B.
x^6
C.
x^7
D.
x^8
Show solution
Solution
Using the power of a power property, (x^2)^3 = x^(2*3) = x^6.
Correct Answer: B — x^6
Learn More →
Q. What is the value of 2^5 × 2^3?
A.
2^8
B.
2^15
C.
2^2
D.
2^5
Show solution
Solution
Using the property of exponents, a^m × a^n = a^(m+n), we get 2^(5+3) = 2^8.
Correct Answer: A — 2^8
Learn More →
Q. What is the value of 2^5?
Show solution
Q. What is the value of 3^(2x) if x = 1?
Show solution
Solution
3^(2*1) = 3^2 = 9.
Correct Answer: C — 9
Learn More →
Q. What is the value of 3^0?
A.
0
B.
1
C.
3
D.
undefined
Show solution
Solution
Any non-zero number raised to the power of 0 is 1.
Correct Answer: B — 1
Learn More →
Q. What is the value of 4^(x) if x = 3?
A.
16
B.
64
C.
256
D.
1024
Show solution
Solution
4^3 = (2^2)^3 = 2^6 = 64.
Correct Answer: C — 256
Learn More →
Q. What is the value of 4^0?
A.
0
B.
1
C.
4
D.
undefined
Show solution
Solution
Any non-zero number raised to the power of 0 is 1.
Correct Answer: B — 1
Learn More →
Q. What is the value of 5^2 * 5^3?
A.
5^5
B.
5^6
C.
5^7
D.
5^8
Show solution
Solution
Using the property of exponents, 5^2 * 5^3 = 5^(2+3) = 5^5.
Correct Answer: A — 5^5
Learn More →
Q. What is the value of 7^0?
A.
0
B.
1
C.
7
D.
undefined
Show solution
Solution
Any non-zero number raised to the power of 0 is 1.
Correct Answer: B — 1
Learn More →
Q. What is the value of 9^(1/2)?
Show solution
Solution
9^(1/2) = √9 = 3.
Correct Answer: C — 3
Learn More →
Showing 31 to 60 of 62 (3 Pages)
