Answer:
Voltmeter
Explanation:
A voltmeter measures the difference or as you say potential difference of a circuit.
Centripetal acceleration is the acceleration of an object acted upon a force that pulls it toward the center of origin. For constant speed, there is no acceleration, since acceleration is defined as the difference of velocities at an elapsed time. Hence, if speed doubles, then the centripetal acceleration would increase as well.
Refraction is the change in direction of waves that occurs when waves travel from one medium to another. Refraction is always accompanied by a wavelength and speed change. Diffraction is the bending of waves around obstacles and openings.
Answer:
b. Its horizontal velocity component is the same as it was just as it was launched
Explanation:
When the rock is thrown from the upper edge of the cliff, at some angle with the horizontal. There is no any acceleration in horizontal direction, therefore, the horizontal velocity remains the same, whereas there is a constant downward acceleration of the magnitude g= 9.81 m/s^2. This causes the increase in vertical velocity of the rock in downward direction.
therefore true statement just before it hits the ground
b. Its horizontal velocity component is the same as it was just as it was launched.
Answer:
Q = 7837500 Joules.
Explanation:
<u>Cho các dữ liệu sau đây;</u>
Khối lượng = 25 kg
Nhiệt độ ban đầu = 25°C
Nhiệt độ cuối cùng = 100°C
Nhiệt dung riêng = 4,18 * 10³ = 4180 J/kg.K
Để tìm nhiệt lượng cần thiết;
Về mặt toán học, nhiệt dung được cho bởi công thức;
Ở đâu;
- Q là nhiệt dung hoặc nhiệt lượng.
- m đại diện cho khối lượng của một vật.
- c biểu diễn nhiệt dung riêng của nước.
- dt thể hiện sự thay đổi của nhiệt độ.
<u>Chuyển đổi:</u>
Nhiệt độ ban đầu = 25°C đến Kelvin = 273 + 25 = 298 K
Nhiệt độ cuối cùng = 100°C đến Kelvin = 273 + 100 = 373 K
dt = T2 - T1
dt = 373 - 298
dt = 75 Kelvin
Thay các giá trị vào phương trình, ta có;
Q = 7837500 Joules.